OFFSET
0,1
LINKS
Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets
Index entries for linear recurrences with constant coefficients, signature (7,-21,35,-35,21,-7,1).
FORMULA
a(n) = n^6 + 15*n^5 + 100*n^4 + 355*n^3 + 694*n^2 + 689*n + 265.
G.f.: -(265 + 264*x + 135*x^2 + 40*x^3 + 15*x^4 + x^6)/(x-1)^7. - R. J. Mathar, Nov 15 2019
P-recursive: n*a(n) = (n+7)*a(n-1) - a(n-2) with a(0) = 265 and a(1) = 2119. Cf. A094791. - Peter Bala, Jul 25 2021
MATHEMATICA
LinearRecurrence[{7, -21, 35, -35, 21, -7, 1}, {265, 2119, 9403, 30637, 81901, 190435, 398959}, 30] (* Harvey P. Dale, Aug 29 2023 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Benoit Cloitre, Jun 11 2004
STATUS
approved