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URL: https://oeis.org/A377189

⇱ A377189 - OEIS

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A377189
Expansion of 1/(1 - 4*x^2 - 4*x^3)^(5/2).
2
1, 0, 10, 10, 70, 140, 490, 1260, 3570, 9660, 25872, 69300, 182490, 480480, 1252680, 3255252, 8412690, 21655920, 55535480, 141921780, 361577216, 918529040, 2327337740, 5882631040, 14836032770, 37339221192, 93794645700, 235186913780, 588736957920, 1471462327160
OFFSET
0,3
FORMULA
a(0) = 1, a(1) = 0, a(2) = 10; a(n) = (4*(n+3)*a(n-2) + 2*(2*n+9)*a(n-3))/n.
a(n) = Sum_{k=0..floor(n/2)} (-4)^k * binomial(-5/2,k) * binomial(k,n-2*k).
PROG
(PARI) a(n) = sum(k=0, n\2, (-4)^k*binomial(-5/2, k)*binomial(k, n-2*k));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 19 2024
STATUS
approved