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URL: https://oeis.org/A362156

⇱ A362156 - OEIS

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A362156
Expansion of -1/(1 - x * sqrt(1-4*x)).
3
-1, -1, 1, 5, 9, 11, 17, 59, 237, 849, 2861, 9625, 33057, 115753, 410581, 1469325, 5296449, 19216691, 70134489, 257320475, 948545125, 3511308899, 13047504065, 48649662439, 181967395749, 682578873479, 2567177040641, 9678602093387, 36571567691029
OFFSET
0,4
FORMULA
a(n) = -Sum_{k=0..n} (-4)^k * binomial((n-k)/2,k).
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(-1/(1-x*sqrt(1-4*x)))
CROSSREFS
Sequence in context: A314603 A214604 A101284 * A102182 A100141 A314604
KEYWORD
sign,easy
AUTHOR
Seiichi Manyama, Apr 09 2023
STATUS
approved