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A377244
Expansion of (1 - 9*x*(1 - 9*x)^(1/3))^(1/3).
2
1, -3, 0, 36, 351, 2592, 16443, 91368, 438858, 1766124, 6039765, 28371951, 345454146, 5042653380, 61953010137, 648331999074, 6013380216978, 50966902431432, 404617672580886, 3082831238643525, 23168405721857769, 176910812101877094, 1406600430681201138
OFFSET
0,2
FORMULA
a(n) = 9^n * Sum_{k=0..n} (-1)^k * binomial(1/3,k) * binomial(n-4*k/3-1,n-k).
PROG
(PARI) a(n) = 9^n*sum(k=0, n, (-1)^k*binomial(1/3, k)*binomial(n-4*k/3-1, n-k));
CROSSREFS
Cf. A377243.
Sequence in context: A368284 A266168 A276913 * A012775 A157308 A157310
KEYWORD
sign
AUTHOR
Seiichi Manyama, Oct 21 2024
STATUS
approved