OFFSET
0,3
LINKS
J. Conrad, Table of n, a(n) for n = 0..34
Index entries for linear recurrences with constant coefficients, signature (8,-28,56,-70,56,-28,8,-1).
FORMULA
Conjectures: a(n) = n*(90+77*n+140*n^3+210*n^4+98*n^5+15*n^6)/630. G.f.: x*(1+20*x+70*x^2+28*x^3+x^4)/(1-x)^8. - Colin Barker, Jan 09 2012
These conjectures are true, see A179095 for proof.
MATHEMATICA
f[n_] := CoefficientList[ Series[ Sum[ x^k, {k, 0, n - 1}]^8, {x, 0, 2 n + 3}], x][[2 n - 1]]; Array[f, 33] (* Robert G. Wilson v, Jul 30 2010 *)
PROG
(PARI) a(n) = polcoeff(((x^n-1)/(x-1))^8, 2*n-2); \\ Michel Marcus, Feb 17 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Michael A. Jackson, Jun 29 2010
EXTENSIONS
More terms from Robert G. Wilson v, Jul 30 2010
STATUS
approved