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A209197
Column 1 of triangle A209196.
1
1, 4, 32, 487, 11113, 335745, 12607257, 565877928, 29553415078, 1760584360722, 117828762999498, 8752769915058447, 714626485356930711, 63609663369881873031, 6130647517448380412727, 636052622643842997577302, 70679525819378610579659532, 8375262433274665594692923984
OFFSET
1,2
COMMENTS
G.f. of A209196 is exp( Sum_{n>=1} x^n/n * Sum_{k=0..n} binomial(n^2, n*k) * y^k ).
PROG
(PARI) {a(n)=polcoeff(polcoeff(exp(sum(m=1, n, x^m/m*sum(j=0, m, binomial(m^2, m*j)*y^j))+x*O(x^n)), n, x), 1, y)}
for(n=1, 20, print1(a(n), ", "))
CROSSREFS
Sequence in context: A192486 A037964 A089285 * A086906 A034663 A192501
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Mar 05 2012
STATUS
approved