A086683 Number of n X n {-1,0,1} matrices modulo cyclic permutations of the rows.
1, 3, 45, 6579, 10763361, 169457722083, 25015772614247325, 34185618461516789943315, 429210477536564292209765507601, 49269609804781974438694405096704997875, 51537752073201133103646184766360896456864366605, 490093718158481239203594498957165010835856989328505008243
Offset: 0
Keywords
Links
- Andrew Howroyd, Table of n, a(n) for n = 0..40
Programs
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PARI
a(n) = if(n<1, n==0, sumdiv(n, d, eulerphi(d)*3^(n^2/d))/n);
Formula
a(n) = (1/n)*Sum_{ d divides n } phi(d)*3^(n^2/d) for n > 0.
Extensions
a(0)=1 prepended and terms a(7) and beyond from Andrew Howroyd, Jul 08 2018