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A381752
Expansion of exp( Sum_{k>=1} binomial(10*k-1,2*k-1) * x^k/k ).
5
1, 9, 525, 44067, 4338765, 467396050, 53346810991, 6339179481480, 775994115988525, 97182642466115275, 12392633418043399130, 1603634650155295053250, 210047857493659698690575, 27795006677556725604853840, 3710220786174094422360657000, 498998879378383167317202612400
OFFSET
0,2
FORMULA
a(0) = 1; a(n) = (1/n) * Sum_{k=1..n} binomial(10*k-1,2*k-1) * a(n-k).
PROG
(PARI) my(N=20, x='x+O('x^N)); Vec(exp(sum(k=1, N, binomial(10*k-1, 2*k-1)*x^k/k)))
KEYWORD
nonn,easy
AUTHOR
Seiichi Manyama, Mar 06 2025
STATUS
approved