login
a(n) = n^7 - n.
5

%I #22 Sep 08 2022 08:45:32

%S 0,0,126,2184,16380,78120,279930,823536,2097144,4782960,9999990,

%T 19487160,35831796,62748504,105413490,170859360,268435440,410338656,

%U 612220014,893871720,1279999980,1801088520,2494357866,3404825424,4586471400,6103515600,8031810150

%N a(n) = n^7 - n.

%C All the terms are divisible by 3.

%H Vincenzo Librandi, <a href="/A133499/b133499.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (8,-28,56,-70,56,-28,8,-1).

%F G.f.: 42*x^2*(3+28*x+58*x^2+28*x^3+3*x^4) / (x-1)^8 . - _R. J. Mathar_, Mar 13 2015

%F a(n) = 42*A030180(n). - _Philippe Deléham_, Mar 17 2016

%e If n=2, then n^7 - n = 126.

%e If n=13, then n^7 - n = 62748504.

%t Table[n^7 - n, {n, 0, 40}] (* and *) LinearRecurrence[{8, -28, 56, -70, 56, -28, 8, -1}, {0, 0, 126, 2184, 16380, 78120, 279930, 823536}, 40] (* _Vladimir Joseph Stephan Orlovsky_, Feb 20 2012 *)

%o (Magma) [n^7-n: n in [0..40]]; // _Vincenzo Librandi_, May 02 2011

%Y Cf. A030180, A061167.

%K nonn,easy

%O 0,3

%A _Parthasarathy Nambi_, Dec 01 2007

%E Corrected and extended by _Jonathan Vos Post_, Dec 02 2007