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A378484
Expansion of (Sum_{k>=0} binomial(4*k,k) * x^k)^4.
4
1, 16, 208, 2480, 28176, 310336, 3344688, 35472672, 371570320, 3853862080, 39650662720, 405221752112, 4117879215472, 41643345090240, 419362920305952, 4207604570770752, 42079232716865424, 419609034657373120, 4173470598366784960, 41413032430984848832, 410071444666659404352
OFFSET
0,2
LINKS
FORMULA
a(n) = Sum_{i+j+k+l=n, i,j,k,l >= 0} binomial(4*i,i) * binomial(4*j,j) * binomial(4*k,k) * binomial(4*l,l).
G.f.: B(x)^4 where B(x) is the g.f. of A005810.
27*a(n) - 256*a(n-1) = 18*A078995(n) + 8*A005810(n) for n > 0.
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(sum(k=0, N, binomial(4*k, k)*x^k)^4)
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Nov 28 2024
STATUS
approved