A299337 Expansion of 1 / ((1 - x)^7*(1 + x)^5).

1, 2, 8, 14, 35, 56, 112, 168, 294, 420, 672, 924, 1386, 1848, 2640, 3432, 4719, 6006, 8008, 10010, 13013, 16016, 20384, 24752, 30940, 37128, 45696, 54264, 65892, 77520, 93024, 108528, 128877, 149226, 175560, 201894, 235543, 269192, 311696, 354200, 407330

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (2,4,-10,-5,20,0,-20,5,10,-4,-2,1).

Formula

a(n) = (2*n^6 + 72*n^5 + 1040*n^4 + 7680*n^3 + 30368*n^2 + 60288*n + 46080) / 46080 for n even.

a(n) = (2*n^6 + 72*n^5 + 1010*n^4 + 6960*n^3 + 24278*n^2 + 39048*n + 20790) / 46080 for n odd.

a(n) = 2*a(n-1) + 4*a(n-2) - 10*a(n-3) - 5*a(n-4) + 20*a(n-5) - 20*a(n-7) + 5*a(n-8) + 10*a(n-9) - 4*a(n-10) - 2*a(n-11) + a(n-12) for n>11.

Prog

(PARI) Vec(1 / ((1 - x)^7*(1 + x)^5) + O(x^40))

Crossrefs

Cf. A001769, A060099, A299335, A299336, A299338.

Sequence in context: A250554 A046959 A086177 * A332611 A162484 A333575

Adjacent sequences: A299334 A299335 A299336 * A299338 A299339 A299340

Keyword

nonn,easy

Author

Colin Barker, Feb 07 2018

Status

approved