A246987 Expansion of (1-11*x+34*x^2-21*x^3+2*x^4)/((1-x)*(1-2*x)*(1-4*x)*(1-5*x)*(1-6*x)).

1, 7, 39, 206, 1087, 5832, 31949, 178486, 1013667, 5832452, 33896809, 198496866, 1168995647, 6913808272, 41021119269, 243974552846, 1453712656027, 8674107635292, 51813825111329, 309768931954426, 1853203840458807, 11092815661905512, 66427422581744989, 397927440625389606, 2384420217810707987

Offset

0,2

Links

Colin Barker, Table of n, a(n) for n = 0..1000

A. Prasad, Equivalence classes of nodes in trees and rational generating functions, arXiv preprint arXiv:1407.5284 [math.CO], 2014

Index entries for linear recurrences with constant coefficients, signature (18,-121,372,-508,240).

Formula

a(n) = (1 - 3*2^(2+n) + 7*2^(1+2*n) + 3*5^n + 6^(1+n)) / 12. - Colin Barker, Jun 06 2015

Prog

(PARI) Vec((2*x^4-21*x^3+34*x^2-11*x+1)/(-240*x^5+508*x^4-372*x^3+121*x^2-18*x+1) + O(x^40)) \\ Colin Barker, Jun 06 2015

Crossrefs

Sequence in context: A026708 A016127 A099460 * A322876 A092923 A164550

Adjacent sequences: A246984 A246985 A246986 * A246988 A246989 A246990

Keyword

nonn,easy

Author

N. J. A. Sloane, Sep 15 2014

Status

approved