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A108991
Main diagonal of triangle A108990, in which the g.f. of row n, R_n(x), satisfies: [x^k] R_{n+1}(x) = [x^k] (1 + x*R_n(x))^(n+1) for k=0..n+1.
6
1, 1, 3, 22, 287, 5496, 139727, 4447234, 170501039, 7661336692, 395314147319, 23054541596934, 1500572569678932, 107886158725753318, 8494969789519239340, 727287072573544716489, 67284371697225428990319
OFFSET
0,3
PROG
(PARI) {a(n)=local(F=1+x*O(x^n)); for(m=1, n, F=(1+x*F)^m); polcoeff(F, n)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jun 15 2005
STATUS
approved