A017023 a(n) = (7*n + 3)^7.

2187, 10000000, 410338673, 4586471424, 27512614111, 114415582592, 373669453125, 1028071702528, 2488651484819, 5455160701056, 11047398519097, 20971520000000, 37725479487783, 64847759419264

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

From G. C. Greubel, Oct 17 2023: (Start)

G.f.: (2187 + 9982504*x + 330399909*x^2 + 1583639568*x^3 + 1750478653*x^4 + 456781416*x^5 + 19356099*x^6 + 16384*x^7)/(1-x)^8.

E.g.f.: (2187 + 9997813*x + 195170430*x^2 + 564242203*x^3 + 482865110*x^4 + 155531978*x^5 + 19765032*x^6 + 823543*x^7)*exp(x). (End)

Mathematica

(7*Range[0, 30]+3)^7 (* or *) LinearRecurrence[{8, -28, 56, -70, 56, -28, 8, -1}, {2187, 10000000, 410338673, 4586471424, 27512614111, 114415582592, 373669453125, 1028071702528}, 30] (* Harvey P. Dale, Jul 07 2020 *)

Prog

(Magma) [(7*n+3)^7: n in [0..30]]; // Vincenzo Librandi, Jul 14 2011
(SageMath) [(7*n+3)^7 for n in range(41)] # G. C. Greubel, Oct 17 2023

Crossrefs

Cf. A017017 - A017022, A017024 - A017028.

Sequence in context: A223980 A223575 A184693 * A017107 A018875 A017203

Adjacent sequences: A017020 A017021 A017022 * A017024 A017025 A017026

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved