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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A318257 Triangle read by rows, expansion of the e.g.f. given below related to partitions of {1,2,...,5n} into sets of size 5, nonzero coefficients of z.

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%I A318257 #9 Aug 26 2018 05:31:22
%S A318257 1,0,1,0,1,126,0,1,3003,126126,0,1,107882,23279256,488864376,0,1,
%T A318257 3321890,5319906900,412275623760,5194672859376,0,1,107746281,
%U A318257 1394769716340,369277150181940,14687937509885640,123378675083039376
%N A318257 Triangle read by rows, expansion of the e.g.f. given below related to partitions of {1,2,...,5n} into sets of size 5, nonzero coefficients of z.
%e A318257 [0] [1]
%e A318257 [1] [0, 1]
%e A318257 [2] [0, 1,     126]
%e A318257 [3] [0, 1,    3003,     126126]
%e A318257 [4] [0, 1,  107882,   23279256,    488864376]
%e A318257 [5] [0, 1, 3321890, 5319906900, 412275623760, 5194672859376]
%p A318257 CL := p -> PolynomialTools:-CoefficientList(p, x):
%p A318257 FL := p -> ListTools:-Flatten(p):
%p A318257 f := z -> (1/5)*(exp(z)+2*(+exp(1/4*z*(5^(1/2)-1))*cos(1/4*z*2^(1/2)*
%p A318257 (5+5^(1/2))^(1/2))+exp(-1/4*z*(5^(1/2)+1))*cos(1/4*z*2^(1/2)*(5-5^(1/2))^(1/2)))):
%p A318257 gf := exp(x*(f(z)-1)): ser := series(gf, z, 48):
%p A318257 FL([seq(CL(sort(expand((5*n)!*coeff(ser, z, n*5)), [x], ascending)),n=0..7)]);
%Y A318257 Cf. A048993 (m=1), A156289 (m=2), A291451 (m=3), A291452 (m=4), this seq (m=5).
%K A318257 nonn,tabl
%O A318257 0,6
%A A318257 _Peter Luschny_, Aug 22 2018