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A369511 Expansion of (1/x) * Series_Reversion( x * ((1-x)^2-x^3)^2 ). 1
1, 4, 26, 206, 1815, 17082, 168159, 1710234, 17828973, 189504744, 2045971440, 22374997320, 247344411792, 2759394009008, 31027178033064, 351270123392892, 4000793799046578, 45809545263096832, 527010005799822844, 6088666065809281348, 70612995488695876634 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
FORMULA
a(n) = (1/(n+1)) * Sum_{k=0..floor(n/3)} binomial(2*n+k+1,k) * binomial(5*n-k+3,n-3*k).
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(serreverse(x*((1-x)^2-x^3)^2)/x)
(PARI) a(n) = sum(k=0, n\3, binomial(2*n+k+1, k)*binomial(5*n-k+3, n-3*k))/(n+1);
CROSSREFS
Cf. A369214.
Sequence in context: A321586 A206391 A368968 * A228966 A291533 A363363
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jan 25 2024
STATUS
approved

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Last modified July 22 13:14 EDT 2024. Contains 374499 sequences. (Running on oeis4.)