All Stories

  1. Central stable range one for elements and rings

    Article • São Paulo Journal of Mathematical Sciences, June 2025, Springer Science + Business Media

    Ph D Grigore Calugareanu

  2. An idempotent not conjugate with its complementary idempotent

    Article • Annals of the Alexandru Ioan Cuza University - Mathematics, June 2025, Editura Universitatii Alexandru Ioan Cuza din Iasi

    Ph D Grigore Calugareanu

  3. On perspective Abelian groups

    Article • Communications in Algebra, February 2025, Taylor & Francis

    Ph D Grigore Calugareanu

  4. Matrix invertible extensions over commutative rings. Part I: General theory

    Article • Journal of Pure and Applied Algebra, January 2025, Elsevier

    Ph D Grigore Calugareanu

  5. On the equation $a^{2}x=a$ in unital rings

    Article • International Electronic Journal of Algebra, September 2024, The International Electronic Journal of Algebra

    Ph D Grigore Calugareanu

  6. 2-Products of Idempotent by Nilpotent Matrices

    Article • Bulletin of the Iranian Mathematical Society, July 2024, Springer Science + Business Media

    Ph D Grigore Calugareanu

  7. The formula $$ABA=Tr(AB)A$$ for matrices

    Article • Beiträge zur Algebra und Geometrie / Contributions to Algebra and Geometry, June 2024, Springer Science + Business Media

    Ph D Grigore Calugareanu

  8. Idempotents which are products of two nilpotents

    Article • Special Matrices, January 2024, De Gruyter

    Ph D Grigore Calugareanu

  9. Abelian groups with C2

    Article • Journal of Algebra and Its Applications, December 2023, World Scientific Pub Co Pte Lt

    Ph D Grigore Calugareanu

  10. Similarity for 2 × 2 Matrices Obtained by Clockwise “Rotation”

    Article • Mathematica Pannonica, December 2023, Akademiai Kiado

    Ph D Grigore Calugareanu

  11. Dependent rings

    Article • Rendiconti del Circolo Matematico di Palermo Series 2, May 2023, Springer Science + Business Media

    Ph D Grigore Calugareanu

  12. Unipotent diagonalization of matrices

    Article • International Electronic Journal of Algebra, April 2023, The International Electronic Journal of Algebra

    Ph D Grigore Calugareanu

  13. On unit stable range matrices

    Article • ANNALI DELL UNIVERSITA DI FERRARA, March 2023, Springer Science + Business Media

    Ph D Grigore Calugareanu

  14. Utumi Abelian groups

    Article • Rendiconti del Seminario Matematico della Università di Padova, February 2023, European Mathematical Publishing House

    Ph D Grigore Calugareanu

  15. Rings Whose Clean Elements are Uniquely Clean

    Article • Mediterranean Journal of Mathematics, December 2022, Springer Science + Business Media

    Ph D Grigore Calugareanu

  16. On idempotent stable range 1 matrices

    Article • Special Matrices, January 2022, De Gruyter

    Ph D Grigore Calugareanu

  17. 3×3 idempotent matrices over some domains and a conjecture on nil-clean matrices

    Article • Annals of the Alexandru Ioan Cuza University - Mathematics, January 2022, Editura Universitatii Alexandru Ioan Cuza din Iasi

    Ph D Grigore Calugareanu

  18. On Zero Determinant Matrices that are Full

    Article • Mathematica Pannonica, October 2021, Akademiai Kiado

    Ph D Grigore Calugareanu

  19. Singular matrices that are products of two idempotents or products of two nilpotents

    Article • Special Matrices, September 2021, De Gruyter

    Ph D Grigore Calugareanu

  20. ABELIAN GROUPS WITH LEFT COMORPHIC ENDOMORPHISM RINGS

    Article • International Electronic Journal of Algebra, July 2021, The International Electronic Journal of Algebra

    Ph D Grigore Calugareanu

  21. Rings with fine nilpotents

    Article • ANNALI DELL UNIVERSITA DI FERRARA, July 2021, Springer Science + Business Media

    Ph D Grigore Calugareanu

  22. On Unit Fine Rings

    Article • Mediterranean Journal of Mathematics, April 2021, Springer Science + Business Media

    Ph D Grigore Calugareanu

  23. Are nil-clean 3 × 3 integral matrices, exchange?

    Article • Annals of the Alexandru Ioan Cuza University - Mathematics, January 2021, Editura Universitatii Alexandru Ioan Cuza din Iasi

    Ph D Grigore Calugareanu

  24. The nil-clean 2 × 2 integral units

    Article • Hacettepe Journal of Mathematics and Statistics, December 2020, Hacettepe Journal of Mathematics and Statistics

    Ph D Grigore Calugareanu

  25. Jacobsons Lemma fails for nil-clean 2 × 2 integral matrices

    Article • Analele ştiinţifice ale Universităţii "Ovidius" Constanţa Seria Matematică, December 2020, De Gruyter

    Ph D Grigore Calugareanu

  26. Rings with fine idempotents

    Article • Journal of Algebra and Its Applications, October 2020, World Scientific Pub Co Pte Lt

    Ph D Grigore Calugareanu

  27. Solitary subgroups of Abelian groups

    Article • Expositiones Mathematicae, October 2020, Elsevier

    Ph D Grigore Calugareanu

  28. Trace 1, 2×2 matrices over principal ideal domains are exchange

    Article • Carpathian Journal of Mathematics, September 2020, Technical University of Cluj Napoca, North University Center of Baia Mare

    Ph D Grigore Calugareanu

  29. Matrices that are similar to their inverses

    Article • The Mathematical Gazette, March 2020, Cambridge University Press

    Ph D Grigore Calugareanu

  30. Strictly Invariant Submodules

    Article • Mediterranean Journal of Mathematics, July 2019, Springer Science + Business Media

    Ph D Grigore Calugareanu

  31. Idempotent matrices with invertible transpose

    Article • Georgian Mathematical Journal, June 2019, De Gruyter

    Ph D Grigore Calugareanu

  32. A new class of nil-clean elements which are exchange

    Article • Beiträge zur Algebra und Geometrie / Contributions to Algebra and Geometry, February 2019, Springer Science + Business Media

    Ph D Grigore Calugareanu

  33. Abelian groups with left morphic endomorphism ring

    Article • Journal of Algebra and Its Applications, August 2018, World Scientific Pub Co Pte Lt

    Ph D Grigore Calugareanu

  34. Subgroups generated by images of endomorphisms of Abelian groups and duality

    Article • Journal of Group Theory, June 2018, De Gruyter

    Ph D Grigore Calugareanu, Andrey Chekhlov

  35. Tripotents: a class of strongly clean elements in rings

    Article • Analele ştiinţifice ale Universităţii "Ovidius" Constanţa Seria Matematică, March 2018, De Gruyter

    Ph D Grigore Calugareanu

  36. Clean integral 2 × 2 matrices

    Article • Studia Scientiarum Mathematicarum Hungarica, March 2018, Akademiai Kiado

    Ph D Grigore Calugareanu

  37. Strongly inert subgroups of abelian groups

    Article • Rendiconti del Seminario Matematico della Università di Padova, December 2017, European Mathematical Publishing House

    Ph D Grigore Calugareanu

  38. Uniquely clean 2×2 invertible integral matrices

    Article • Studia Universitatis Babes-Bolyai Mathematica, September 2017, Babes-Bolyai University

    Ph D Grigore Calugareanu

  39. UN-rings

    Article • Journal of Algebra and Its Applications, November 2016, World Scientific Pub Co Pte Lt

    Ph D Grigore Calugareanu

  40. Some matrix completions over integral domains

    Article • Linear Algebra and its Applications, October 2016, Elsevier

    Ph D Grigore Calugareanu

  41. Fine rings: A new class of simple rings

    Article • Journal of Algebra and Its Applications, August 2016, World Scientific Pub Co Pte Lt

    Ph D Grigore Calugareanu

  42. Sums of nilpotent matrices

    Article • Linear and Multilinear Algebra, March 2016, Taylor & Francis

    Ph D Grigore Calugareanu

  43. Pseudo injective abelian groups

    Article • Forum Mathematicum, January 2015, De Gruyter

    Ph D Grigore Calugareanu, Phill Schultz

  44. STRONGLY INVARIANT SUBGROUPS

    Article • Glasgow Mathematical Journal, December 2014, Cambridge University Press

    Ph D Grigore Calugareanu

  45. A nil-clean 2 × 2 matrix over the integers which is not clean

    Article • Journal of Algebra and Its Applications, April 2014, World Scientific Pub Co Pte Lt

    Ph D Grigore Calugareanu

  46. Nil-clean matrix rings

    Article • Linear Algebra and its Applications, November 2013, Elsevier

    Ph D Grigore Calugareanu

  47. Between Morphic and Hopfian

    Article • Analele ştiinţifice ale Universităţii "Ovidius" Constanţa Seria Matematică, January 2013, De Gruyter

    Ph D Grigore Calugareanu

  48. Type 1 representable lattices of dimension at most 4

    Article • Algebra Universalis, February 2012, Springer Science + Business Media

    Ph D Grigore Calugareanu

  49. On Abelian Groups with commutative clean endomorphism rings

    Article • Annals of the Alexandru Ioan Cuza University - Mathematics, January 2012, De Gruyter

    Ph D Grigore Calugareanu

  50. Realization Theorems for Triangular Rings

    Article • Annals of the Alexandru Ioan Cuza University - Mathematics, January 2011, De Gruyter

    Ph D Grigore Calugareanu

  51. MODULES WITH ABELIAN ENDOMORPHISM RINGS

    Article • Bulletin of the Australian Mathematical Society, June 2010, Cambridge University Press

    Ph D Grigore Calugareanu

  52. MORPHIC ABELIAN GROUPS

    Article • Journal of Algebra and Its Applications, April 2010, World Scientific Pub Co Pte Lt

    Ph D Grigore Calugareanu

  53. Rings with Lattices of Idempotents

    Article • Communications in Algebra, March 2010, Taylor & Francis

    Ph D Grigore Calugareanu

  54. SPLIT-EXTENSIONS OF EXCHANGE RINGS: A DIRECT PROOF

    Article • Journal of Algebra and Its Applications, October 2009, World Scientific Pub Co Pte Lt

    Ph D Grigore Calugareanu

  55. Every Abelian group is determined by a subgroup lattice

    Article • Studia Scientiarum Mathematicarum Hungarica, March 2008, Akademiai Kiado

    Ph D Grigore Calugareanu

  56. A solution to a problem on lattice isomorphic Abelian groups

    Article • January 2008, De Gruyter

    Ph D Grigore Calugareanu

  57. Endomorphisms and automorphisms of squares of abelian groups

    Article • January 2008, De Gruyter

    Ph D Grigore Calugareanu

  58. Abelian groups determined by subgroup lattices of direct powers

    Article • Archiv der Mathematik, February 2006, Springer Science + Business Media

    Ph D Grigore Calugareanu

  59. Abelian groups whose subgroup lattice is the union of two intervals

    Article • Journal of the Australian Mathematical Society, February 2005, Cambridge University Press

    Ph D Grigore Calugareanu

  60. ABELIAN GROUPS WITH SEMI-LOCAL ENDOMORPHISM RING

    Article • Communications in Algebra, January 2002, Taylor & Francis

    Ph D Grigore Calugareanu