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A280782
Number of irreducible matrices X of all sizes with nonnegative integral entries satisfying X^2 = nX.
1
1, 2, 6, 15, 42, 99, 262, 633, 1592, 3897, 9697, 23767, 58804, 144541
OFFSET
1,2
LINKS
Jakob Zimmermann, Counting quasi-idempotent irreducible integral matrices, arXiv:1701.03699 [math.CO], 2017.
CROSSREFS
Cf. A280783.
Sequence in context: A139379 A236110 A362566 * A307308 A065178 A178936
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Jan 20 2017
EXTENSIONS
Definition corrected by N. J. A. Sloane, Jan 23 2017 at the suggestion of Jakob Zimmermann
a(14) from Jakob Zimmermann, Jan 23 2017
STATUS
approved