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A280783
Number of irreducible matrices X of all sizes with nonnegative integral entries satisfying X^2 = nX, counted up to a permutation of basis vectors.
1
1, 2, 4, 8, 16, 27, 51, 83, 140, 225, 369
OFFSET
1,2
LINKS
Jakob Zimmermann, Counting quasi-idempotent irreducible integral matrices, arXiv:1701.03699 [math.CO], 2017.
CROSSREFS
Cf. A280782.
Sequence in context: A342130 A258624 A236292 * A104899 A057975 A260881
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
STATUS
approved