A186184 Expansion of 1/(1 - x*A002296(x)).

1, 1, 2, 10, 89, 1002, 12592, 168805, 2363241, 34138860, 505042286, 7612594936, 116492572621, 1804984878387, 28260999959595, 446441276449715, 7106718529937710, 113886198966545724

Offset

0,3

Links

Table of n, a(n) for n=0..17.

Vladimir Kruchinin and D. V. Kruchinin, Composita and their properties , arXiv:1103.2582 [math.CO], 2011-2013.

Formula

a(n) = Sum_{k=1..n} (k/(6*n-5*k))*binomial(7*n-6*k-1, n-k), n > 0.

Maple

A186184 := proc(n)
   if n = 0 then
      1;
   else
      add( k/(6*n-5*k)*binomial(7*n-6*k-1, n-k), k=1..n) ;
   end if;
end proc:
seq(A186184(n), n=0..20) ; # R. J. Mathar, Feb 26 2011

Mathematica

Join[{1}, Table[Sum[k/(6n-5k) Binomial[7n-6k-1, n-k], {k, n}], {n, 30}]] (* Harvey P. Dale, Aug 29 2012 *)

Crossrefs

Sequence in context: A270923 A096658 A346371 * A326554 A055779 A363425

Adjacent sequences: A186181 A186182 A186183 * A186185 A186186 A186187

Keyword

nonn

Author

Vladimir Kruchinin, Feb 14 2011

Status

approved