A017335 a(n) = (10*n + 5)^7.

78125, 170859375, 6103515625, 64339296875, 373669453125, 1522435234375, 4902227890625, 13348388671875, 32057708828125, 69833729609375, 140710042265625, 266001988046875, 476837158203125, 817215093984375, 1347646586640625, 2149422977421875, 3329565857578125

Offset

0,1

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.: 78125*(x+1)*(x^6 + 2178*x^5 + 58479*x^4 + 201244*x^3 + 58479*x^2 + 2178*x + 1)/(x-1)^8. - Colin Barker, Nov 13 2012

From Amiram Eldar, Apr 18 2023: (Start)

a(n) = A017329(n)^7.

a(n) = 5^7 * A016759(n).

Sum_{n>=0} 1/a(n) = 127*zeta(7)/10000000.

Sum_{n>=0} (-1)^n/a(n) = 61*Pi^7/14400000000. (End)

Mathematica

Table[(10*n + 5)^7, {n, 0, 20}] (* Amiram Eldar, Apr 18 2023 *)

Prog

(Magma) [(10*n+5)^7: n in [0..25]]; // Vincenzo Librandi, Aug 02 2011

Crossrefs

Cf. A013665, A016759, A017329.

Sequence in context: A017131 A017227 A265935 * A017455 A017587 A237565

Adjacent sequences: A017332 A017333 A017334 * A017336 A017337 A017338

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved