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A186183 Expansion of 1/(1-x*A002295(x)). 0
1, 1, 2, 9, 68, 646, 6857, 77695, 919642, 11233858, 140544189, 1791614714, 23187320736, 303861373679, 4023883823059, 53762917329659, 723854999871943, 9811154512175468, 133762940465746744, 1833187046654598058, 25239961633188882896 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..20.

Vladimir Kruchinin, D. V. Kruchinin, Composita and their properties, arXiv:1103.2582

FORMULA

a(n) = sum(k=1..n, k/(5*n-4*k) * binomial(6*n-5*k-1,n-k)) if n>0; a(0)=1.

MAPLE

a:= n-> `if` (n=0, 1, add (k/(5*n-4*k) *binomial (6*n-5*k-1, n-k), k=1..n)):

seq (a(n), n=0..30);

PROG

(PARI) a(n)=max(1, sum(k=1, n, k/(5*n-4*k)*binomial(6*n-5*k-1, n-k)))

CROSSREFS

Sequence in context: A296793 A336588 A322612 * A295239 A120020 A200248

Adjacent sequences:  A186180 A186181 A186182 * A186184 A186185 A186186

KEYWORD

nonn

AUTHOR

Vladimir Kruchinin, Feb 14 2011

STATUS

approved

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Last modified July 30 10:09 EDT 2021. Contains 346359 sequences. (Running on oeis4.)