A376803 Expansion of 1/((1 - x)^3 - 9*x^2)^(1/3).
1, 1, 4, 13, 49, 187, 736, 2941, 11908, 48682, 200584, 831712, 3466867, 14515411, 61005634, 257238349, 1087792225, 4611606373, 19594364860, 83421726877, 355801896895, 1519998686401, 6503081167372, 27859917707863, 119502218725576, 513173645933326
Offset: 0
Keywords
Programs
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PARI
my(N=30, x='x+O('x^N)); Vec(1/((1-x)^3-9*x^2)^(1/3))
Formula
a(n) = Sum_{k=0..floor(n/2)} (-9)^k * binomial(-1/3,k) * binomial(n+k,n-2*k).