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%I #22 Mar 13 2024 10:33:28
%S 0,7,6272,750141,39337984,1313046875,32934190464,678223072849,
%T 12089663946752,193010051319183,2824752490000000,38532504363714053,
%U 495958345459089408,6079641716636816419,71493870602660352896
%N a(n) = n^7 * 7^n.
%H Vincenzo Librandi, <a href="/A098803/b098803.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 (56,-1372,19208,-168070,941192,-3294172,6588344,-5764801).
%F G.f.: 7*x*(117649*x^6 +2016840*x^5 +2859591*x^4 +828688*x^3 +58359*x^2 +840*x +1) / (7*x -1)^8. - _Colin Barker_, Apr 30 2013
%e a(1) = 1^7 * 7^1 = 7.
%e a(2) = 2^7 * 7^2 = 6272.
%t Table[n^7*7^n, {n, 1, 20}] (* _Stefan Steinerberger_, Mar 06 2006 *)
%o (Magma) [7^n*n^7: n in [0..20]]; // _Vincenzo Librandi_, Oct 27 2011
%o (PARI) a(n)=n^7*7^n \\ _Charles R Greathouse IV_, Oct 07 2015
%Y Cf. A007758, A062074, A062075.
%K nonn,easy
%O 0,2
%A _Parthasarathy Nambi_, Oct 05 2004
%E More terms from _Stefan Steinerberger_, Mar 06 2006
%E Offset changed from 1 to 0 by _Vincenzo Librandi_, Oct 27 2011