1,2

Table of n, a(n) for n=1..14.

Jakob Zimmermann, Counting quasi-idempotent irreducible integral matrices, arXiv:1701.03699 [math.CO], 2017.

Cf. A280783.

Sequence in context: A121328 A139379 A236110 * A307308 A065178 A178936

Adjacent sequences: A280779 A280780 A280781 * A280783 A280784 A280785

nonn,more

N. J. A. Sloane, Jan 20 2017

Definition corrected by N. J. A. Sloane, Jan 23 2017 at the suggestion of Jakob Zimmermann

a(14) from Jakob Zimmermann, Jan 23 2017

approved