OFFSET
1,7
EXAMPLE
Triangle begins:
1;
1;
1, 0, 1;
1, 3, 4;
1, 15, 10, 0, 6;
1, 45, 40, 45, 36;
1, 105, 175, 315, 126, 105, 120;
1, 315, 616, 1890, 336, 2520, 960, 0, 0, 0, 0, 0, 0, 0, 336;
...
PROG
(PARI)
permcount(v) = {my(m=1, s=0, k=0, t); for(i=1, #v, t=v[i]; k=if(i>1&&t==v[i-1], k+1, 1); m*=t*k; s+=t); s!/m}
G(n)={my(s=0); forpart(p=n, if(sum(i=1, #p, p[i]-1)%2==0, my(d=lcm(Vec(p))); s+=x^d*permcount(p)/eulerphi(d))); s}
for(n=1, 10, print(Vecrev(G(n)/x)))
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Andrew Howroyd, Jul 03 2018
STATUS
approved