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A365847
Expansion of (1/x) * Series_Reversion( x*(1-x)^4/(1+x)^4 ).
5
1, 8, 96, 1368, 21440, 356968, 6197408, 110947768, 2033381760, 37963483592, 719495148768, 13806129179928, 267693334199616, 5236670783633960, 103227182363423008, 2048451544990578552, 40888361539777714944, 820400146864231266184
OFFSET
0,2
FORMULA
a(n) = (1/(n+1)) * Sum_{k=0..n} binomial(4*n+k+3,k) * binomial(4*(n+1),n-k).
Conjecture: g.f.: B^4, where B is the g.f. of A260332.
PROG
(PARI) a(n) = sum(k=0, n, binomial(4*n+k+3, k)*binomial(4*(n+1), n-k))/(n+1);
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 20 2023
STATUS
approved