OFFSET
7,2
COMMENTS
Sum_{k=0..49} a(n)=A054976(7).
FORMULA
G.f. : Z(S_7 X S_7; x_1, x_2, ...)-2*Z(S_7 X S_6; x_1, x_2, ...)+Z(S_6 X S_6; x_1, x_2, ...) if we replace x_i by 1+x^i, where Z(S_i X S_j; x_1, x_2, ...) is cycle index of Cartesian product of symmetric groups S_i and S_j of degree i and j, respectively.
CROSSREFS
KEYWORD
fini,full,nonn
AUTHOR
Vladeta Jovovic, Aug 04 2000
EXTENSIONS
More terms from Sean A. Irvine, Apr 14 2022
STATUS
approved