publications

2025

1. Preprint

   On the classification of triply transitive strongly-regular graphs

   Allen Herman, Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Submitted, 2025

   arXiv Bib

   @article{Talgebra,
     title = {On the classification of triply transitive strongly-regular graphs},
     author = {Herman, Allen and Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Submitted},
     year = {2025},
   }

2. Distance-regular graphs arising from the transitive action of PSL(2,q) on 2-subsets of PG(1,q)

   Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Journal of Algebraic Combinatorics, 2025

   Bib URL PDF

   @article{psl,
     title = {Distance-regular graphs arising from the transitive action of PSL(2,q) on 2-subsets of PG(1,q)},
     author = {Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Journal of Algebraic Combinatorics},
     year = {2025},
     doi = {10.1007/s10801-025-01430-6},
   }

3. Preprint

   The intersection densities of transitive actions of PSL(2,q) with cyclic point stabilizers

   Angelot Behajaina, Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Submitted, 2025

   Bib

   @article{psl2-cyclic-stab,
     title = {The intersection densities of transitive actions of $PSL(2,q)$ with cyclic point stabilizers},
     author = {Behajaina, Angelot and Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Submitted},
     year = {2025},
   }

4. Preprint

   Breaking the symmetries of the derangement graph

   Nancy Neudauer, and Andriaherimanana Sarobidy Razafimahatratra

   Submitted, 2025

   Bib

   @article{symmetrybreaking,
     title = {Breaking the symmetries of the derangement graph},
     author = {Neudauer, Nancy and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Submitted},
     year = {2025},
   }

5. Preprint

   The intersection density of cubic arc-transitive graphs with 2-arc-regular full automorphism group equal to PGL_2(q)

   Karen Meagher, and Andriaherimanana Sarobidy Razafimahatratra

   Combinatorial Theory (accepted), 2025

   arXiv Bib

   @article{psm,
     title = {The intersection density of cubic arc-transitive graphs with 2-arc-regular full automorphism group equal to $PGL_2(q)$},
     author = {Meagher, Karen and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Combinatorial Theory (accepted)},
     year = {2025},
   }

6. On the Terwilliger algebra of the group association scheme of the symmetric group Sym(7)

   Allen Herman, Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Journal of Combinatorial Designs, 2025

   arXiv Bib PDF

   @article{Talgebrb,
     title = {On the Terwilliger algebra of the group association scheme of the symmetric group Sym(7)},
     author = {Herman, Allen and Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Journal of Combinatorial Designs},
     year = {2025},
     dimensions = {true},
   }

7. The intersection density of non-quasiprimitive groups of degree 3p

   Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Discrete Math., 2025

   arXiv Bib PDF

   @article{degree3p,
     title = {The intersection density of non-quasiprimitive groups of degree $3p$},
     author = {Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Discrete Math.},
     year = {2025},
     dimensions = {true},
   }

8. Hamiltonicity of certain vertex-transitive graphs revisited

   Klavdija Kutnar, Dragan Marušič, and Andriaherimanana Sarobidy Razafimahatratra

   Discrete Math., 2025

   Bib URL

   @article{Hcompressioo,
     title = {Hamiltonicity of certain vertex-transitive graphs revisited},
     author = {Kutnar, Klavdija and Marušič, Dragan and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Discrete Math.},
     year = {2025},
     dimensions = {true},
   }

2024

1. Preprint

   On the size of cocliques of some Cayley graphs of GL_2(q)

   Andriaherimanana Sarobidy Razafimahatratra

   Submitted, 2024

   Bib

   @article{Hcompression,
     title = {On the size of cocliques of some Cayley graphs of $GL_2(q)$},
     author = {Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Submitted},
     year = {2024},
     dimensions = {true},
   }

2. Preprint

   On the maximum intersecting sets of the general semilinear group of degree 2

   Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   arXiv preprint arXiv:2402.17687, 2024

   arXiv Bib

   @article{gammal,
     title = {On the maximum intersecting sets of the general semilinear group of degree $2$},
     author = {Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {arXiv preprint arXiv:2402.17687},
     year = {2024},
   }

3. Infinite families of vertex-transitive graphs with prescribed Hamilton compression

   Klavdija Kutnar, Dragan Marušič, and Andriaherimanana Sarobidy Razafimahatratra

   Annals Combin., 2024

   arXiv Bib URL

   @article{Hcompressiop,
     title = {Infinite families of vertex-transitive graphs with prescribed Hamilton compression},
     author = {Kutnar, Klavdija and Marušič, Dragan and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Annals Combin.},
     year = {2024},
     doi = {10.1007/s00026-024-00703-4},
     dimensions = {true}
   }

4. On the intersection spectrum of PSL_2(q)

   Angelot Behajaina, Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   J. Algebraic Combin., 2024

   arXiv Bib URL

   @article{behajaina-psl,
     title = {On the intersection spectrum of $PSL_{2}(q)$},
     author = {Behajaina, Angelot and Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {J. Algebraic Combin.},
     year = {2024},
     doi = {10.1007/s10801-024-01356-5},
     dimensions = {false},
   }

5. On cocliques in commutative Schurian association schemes of the symmetric group

   Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Australasian J. Combin., 2024

   arXiv Bib URL

   @article{cocliquesschurianscheme,
     title = {On cocliques in commutative Schurian association schemes of the symmetric group},
     author = {Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Australasian J. Combin.},
     year = {2024},
   }

6. Intersection density of imprimitive groups of degree pq

   Angelot Behajaina, Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   J. Combin. Theory Ser. A, 2024

   arXiv Bib URL PDF

   @article{degreepq,
     title = {Intersection density of imprimitive groups of degree pq},
     author = {Behajaina, Angelot and Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {J. Combin. Theory Ser. A},
     year = {2024},
     dimensions = {true},
   }

7. A short note on non-diagonalizable vertex-primitive digraphs

   Andriaherimanana Sarobidy Razafimahatratra

   Australas. J. Combin., 2024

   Bib URL PDF

   @article{non-diagonalizable,
     title = {A short note on non-diagonalizable vertex-primitive digraphs},
     author = {Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Australas. J. Combin.},
     year = {2024},
   }

8. The q-Analogue of Zero Forcing for Certain Families of Graphs

   Shaun Fallat, Neha Joshi, Roghayeh Maleki, Karen Meagher, Seyed Ahmad Mojallal, Shahla Nasserasr, Mahsa N. Shirazi, Andriaherimanana Sarobidy Razafimahatratra, and Brett Stevens

   Discrete Appl. Math., 2024

   arXiv Bib URL

   @article{Zq,
     title = {The $q$-Analogue of Zero Forcing for Certain Families of Graphs},
     author = {Fallat, Shaun and Joshi, Neha and Maleki, Roghayeh and Meagher, Karen and Mojallal, Seyed Ahmad and Nasserasr, Shahla and Shirazi, Mahsa N. and Razafimahatratra, Andriaherimanana Sarobidy and Stevens, Brett},
     journal = {Discrete Appl. Math.},
     year = {2024},
     dimensions = {true},
   }

9. On the intersection density of the Kneser Graph K(n,3)

   Karen Meagher, and Andriaherimanana Sarobidy Razafimahatratra

   European J. Combin., 2024

   arXiv Bib URL PDF

   @article{psn,
     title = {On the intersection density of the Kneser Graph $K(n,3)$},
     author = {Meagher, Karen and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {European J. Combin.},
     year = {2024},
     dimensions = {true},
   }

2023

1. Preprint

   On cospectral Cayley graphs on the symmetric group

   Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   submitted, 2023

   Bib

   @article{cospectral-cayley-graphs,
     title = {On cospectral Cayley graphs on the symmetric group},
     author = {Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {submitted},
     year = {2023},
   }

2. On the second eigenvalue of certain Cayley graphs on the symmetric group

   Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Bull. Malays. Math. Sci. Soc., 2023

   arXiv Bib URL

   @article{second-eigenvalues,
     title = {On the second eigenvalue of certain Cayley graphs on the symmetric group},
     author = {Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Bull. Malays. Math. Sci. Soc.},
     volume = {46},
     year = {2023},
     doi = {10.1007/s40840-023-01553-8},
     dimensions = {true},
   }

3. On closed distance magic circulants of valency up to 5

   Blas Fernández, Roghayeh Maleki, Štefko Miklavič, and Andriaherimanana Sarobidy Razafimahatratra

   Discrete Math., 2023

   arXiv Bib URL

   @article{cdm,
     title = {On closed distance magic circulants of valency up to $5$},
     author = {Fernández, Blas and Maleki, Roghayeh and Miklavič, Štefko and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Discrete Math.},
     volume = {346},
     year = {2023},
     doi = {10.1016/j.disc.2023.113581},
     dimensions = {true},
   }

4. On the intersection density of the symmetric group acting on uniform subsets of small size

   Angelot Behajaina, Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Linear Algebra Appl., 2023

   arXiv Bib URL

   @article{behajaina2022intersection,
     title = {On the intersection density of the symmetric group acting on uniform subsets of small size},
     author = {Behajaina, Angelot and Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {Linear Algebra Appl.},
     year = {2023},
     doi = {10.1016/j.laa.2023.01.010},
     dimensions = {true}
   }

5. On the intersection density of primitive groups of degree a product of two odd primes

   Andriaherimanana Sarobidy Razafimahatratra

   J. Combin. Theory Ser. A, 2023

   arXiv Bib URL

   @article{razafimahatratra2021intersection,
     title = {On the intersection density of primitive groups of degree a product of two odd primes},
     author = {Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {J. Combin. Theory Ser. A},
     volume = {194},
     year = {2023},
     doi = {10.1016/j.jcta.2022.105707},
     dimensions = {true}
   }

2022

1. Some Erdos-Ko-Rado results for linear and affine groups of degree two

   Karen Meagher, and A. Sarobidy Razafimahatratra

   The Art of Discrete and Applied Mathematics, 2022

   Bib URL PDF

   @article{Meagher-GL,
     author = {Meagher, Karen and Razafimahatratra, A. Sarobidy},
     title = {Some {E}rdos-{K}o-{R}ado results for linear and affine groups of degree two},
     journal = {The Art of Discrete and Applied Mathematics},
     fjournal = {The Art of Discrete and Applied Mathematics},
     volume = {},
     year = {2022},
     doi = {10.26493/2590-9770.1494.1e4},
     dimensions = {true},
   }

2021

1. The Erdős-Ko-Rado theorem for 2-pointwise and 2-setwise intersecting permutations

   Karen Meagher, and A. Sarobidy Razafimahatratra

   Electron. J. Combin., 2021

   Bib URL

   @article{MR4328908,
     author = {Meagher, Karen and Razafimahatratra, A. Sarobidy},
     title = {The {E}rd\H{o}s-{K}o-{R}ado theorem for 2-pointwise and 2-setwise
                   intersecting permutations},
     journal = {Electron. J. Combin.},
     fjournal = {Electronic Journal of Combinatorics},
     volume = {28},
     year = {2021},
     number = {4},
     pages = {Paper No. 4.10, 21},
     mrclass = {05D10 (05A05)},
     mrnumber = {4328908},
     doi = {10.37236/9556},
     dimensions = {true},
   }

2. Weakly Hadamard diagonalizable graphs

   Mohammad Adm, Khawla Almuhtaseb, Shaun Fallat, Karen Meagher, Shahla Nasserasr, Mahsa N. Shirazi, and A. S. Razafimahatratra

   Linear Algebra Appl., 2021

   Bib URL PDF

   @article{MR4159285,
     author = {Adm, Mohammad and Almuhtaseb, Khawla and Fallat, Shaun and Meagher, Karen and Nasserasr, Shahla and Shirazi, Mahsa N. and Razafimahatratra, A. S.},
     title = {Weakly {H}adamard diagonalizable graphs},
     journal = {Linear Algebra Appl.},
     fjournal = {Linear Algebra and its Applications},
     volume = {610},
     year = {2021},
     pages = {86--119},
     issn = {0024-3795},
     mrclass = {05C50 (15A18 15B34)},
     mrnumber = {4159285},
     mrreviewer = {Shunyi Liu},
     doi = {10.1016/j.laa.2020.09.038},
     dimensions = {true},
   }

3. 3-setwise intersecting families of the symmetric group

   Angelot Behajaina, Roghayeh Maleki, Aina Toky Rasoamanana, and A. Sarobidy Razafimahatratra

   Discrete Math., 2021

   arXiv Bib URL

   @article{MR4262022,
     author = {Behajaina, Angelot and Maleki, Roghayeh and Rasoamanana, Aina Toky and Razafimahatratra, A. Sarobidy},
     title = {3-setwise intersecting families of the symmetric group},
     journal = {Discrete Math.},
     fjournal = {Discrete Mathematics},
     volume = {344},
     year = {2021},
     number = {8},
     pages = {Paper No. 112467, 15},
     issn = {0012-365X},
     mrclass = {05D05 (20B30)},
     mrnumber = {4262022},
     mrreviewer = {Elad Aigner-Horev},
     doi = {10.1016/j.disc.2021.112467},
     dimensions = {true},
   }

4. On triangles in derangement graphs

   Karen Meagher, Andriaherimanana Sarobidy Razafimahatratra, and Pablo Spiga

   J. Combin. Theory Ser. A, 2021

   arXiv Bib URL

   @article{MR4195884,
     author = {Meagher, Karen and Razafimahatratra, Andriaherimanana Sarobidy and Spiga, Pablo},
     title = {On triangles in derangement graphs},
     journal = {J. Combin. Theory Ser. A},
     fjournal = {Journal of Combinatorial Theory. Series A},
     volume = {180},
     year = {2021},
     pages = {Paper No. 105390, 26},
     issn = {0097-3165},
     mrclass = {05C25 (05C69 05D10)},
     mrnumber = {4195884},
     mrreviewer = {Norihide Tokushige},
     doi = {10.1016/j.jcta.2020.105390},
     dimensions = {true},
   }

5. On non-normal subgroup perfect codes

   Behajaina, Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   Australas. J. Combin., 2021

   arXiv Bib URL

   @article{MR4333853,
     author = {Behajaina and Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     title = {On non-normal subgroup perfect codes},
     journal = {Australas. J. Combin.},
     fjournal = {The Australasian Journal of Combinatorics},
     volume = {81},
     year = {2021},
     pages = {474--479},
     issn = {1034-4942},
     mrclass = {05C69},
     mrnumber = {4333853},
     mrreviewer = {T. Tamizh Chelvam},
   }

6. On complete multipartite derangement graphs

   Andriaherimanana Sarobidy Razafimahatratra

   Ars Math. Contemp., 2021

   arXiv Bib URL

   @article{MR4341193,
     author = {Razafimahatratra, Andriaherimanana Sarobidy},
     title = {On complete multipartite derangement graphs},
     journal = {Ars Math. Contemp.},
     fjournal = {Ars Mathematica Contemporanea},
     volume = {21},
     year = {2021},
     number = {1},
     pages = {Paper No. 7, 15},
     issn = {1855-3966},
     mrclass = {05D05 (05C35 05C69 20B05)},
     mrnumber = {4341193},
     doi = {10.26493/1855-3974.2554.856},
     dimensions = {true},
   }

7. Preprint

   No Hilton-Milner type results for linear groups of degree two

   Roghayeh Maleki, and Andriaherimanana Sarobidy Razafimahatratra

   arXiv preprint arXiv:2111.03829, 2021

   arXiv Bib

   @article{maleki2021no,
     title = {No Hilton-Milner type results for linear groups of degree two},
     author = {Maleki, Roghayeh and Razafimahatratra, Andriaherimanana Sarobidy},
     journal = {arXiv preprint arXiv:2111.03829},
     year = {2021},
   }

2020

1. Zero-one laws for k-variable first-order logic of sparse random graphs

   A. S. Razafimahatratra, and M. Zhukovskii

   Discrete Appl. Math., 2020

   arXiv Bib URL

   @article{MR4075521,
     author = {Razafimahatratra, A. S. and Zhukovskii, M.},
     title = {Zero-one laws for {$k$}-variable first-order logic of sparse
                   random graphs},
     journal = {Discrete Appl. Math.},
     fjournal = {Discrete Applied Mathematics. The Journal of Combinatorial
                   Algorithms, Informatics and Computational Sciences},
     volume = {276},
     year = {2020},
     pages = {121--128},
     issn = {0166-218X},
     mrclass = {05C80 (03C13)},
     mrnumber = {4075521},
     mrreviewer = {Vera Koponen},
     doi = {10.1016/j.dam.2019.02.032},
     dimensions = {true},
   }