OFFSET
0,2
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).
FORMULA
From Colin Barker, Jul 20 2017: (Start)
G.f.: x*(39 - 77*x + 111*x^2 - 88*x^3 + 36*x^4 - 6*x^5) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n > 6.
(End)
MATHEMATICA
LinearRecurrence[{7, -21, 35, -35, 21, -7, 1}, {0, 39, 196, 664, 1809, 4250, 8954}, 40] (* Harvey P. Dale, Nov 15 2022 *)
PROG
(PARI) concat(0, Vec(x*(39 - 77*x + 111*x^2 - 88*x^3 + 36*x^4 - 6*x^5) / (1 - x)^7 + O(x^50))) \\ Colin Barker, Jul 20 2017
(PARI) vector(50, n, n*(n+5)^2*(n^3+7*n^2+16*n+28)/48) \\ Derek Orr, Jul 24 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Gregory Gerard Wojnar, Jul 19 2017
STATUS
approved