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A201196
G.f. A(x) satisfies A(x) = 1+x^2/(1-x)*A(x^2/(1-x)).
0
1, 1, 0, 1, 1, 4, 0, 5, 2, 13, 6, 40, 24, 150, 100, 583, 315, 1928, 899, 5781, 2594, 16966, 7857, 51206, 25509, 163112, 86794, 545710, 305266, 1896760, 1102162, 6791877, 4071898, 24940019, 15372173, 93650718, 59059102, 358173049, 229642610, 1387712043, 897620738
OFFSET
0,6
FORMULA
a(n)=sum(k=1..n, binomial(n-k-1,k-1)*a(k-1)), a(0)=1.
PROG
(Maxima)
a(n):=if n=0 then 1 else sum(binomial(n-k-1, k-1)*a(k-1), k, 1, n);
CROSSREFS
Sequence in context: A327545 A306072 A185199 * A377636 A019906 A197251
KEYWORD
nonn
AUTHOR
Vladimir Kruchinin, Nov 28 2011
STATUS
approved