A016999 a(n) = (7*n + 1)^7.

1, 2097152, 170859375, 2494357888, 17249876309, 78364164096, 271818611107, 781250000000, 1954897493193, 4398046511104, 9095120158391, 17565568854912, 32057708828125, 55784660123648

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

Index entries for linear recurrences with constant coefficients, signature (8, -28, 56, -70, 56, -28, 8, -1).

Formula

G.f.: (1 + 2097144*x + 154082187*x^2 + 1186203088*x^3 + 1961635263*x^4 + 785850072*x^5 + 60509029*x^6 + 279936*x^7)/(-1+x)^8. - R. J. Mathar, Jun 24 2009

a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8). - Wesley Ivan Hurt, Jun 26 2022

Mathematica

(7*Range[0, 20]+1)^7 (* or *) LinearRecurrence[{8, -28, 56, -70, 56, -28, 8, -1}, {1, 2097152, 170859375, 2494357888, 17249876309, 78364164096, 271818611107, 781250000000}, 20] (* Harvey P. Dale, Sep 25 2020 *)

Prog

(Magma) [(7*n+1)^7: n in [0..20]]; // Vincenzo Librandi, Jul 13 2011

Crossrefs

Sequence in context: A195236 A068345 A194935 * A017071 A017263 A017371

Adjacent sequences: A016996 A016997 A016998 * A017000 A017001 A017002

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved