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%I #36 Sep 08 2022 08:45:18
%S 1,1,51,211,565,1221,2311,3991,6441,9865,14491,20571,28381,38221,
%T 50415,65311,83281,104721,130051,159715,194181,233941,279511,331431,
%U 390265,456601,531051,614251,706861,809565,923071,1048111,1185441,1335841
%N a(n) = n^4 - 15*n + 15.
%C a(n) == A109009(n) (mod 10). - _Michel Marcus_, Sep 05 2013
%H Vincenzo Librandi, <a href="/A107253/b107253.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F G.f.: x*(1-4*x+56*x^2-44*x^3+15*x^4)/(1-x)^5. - _Vincenzo Librandi_, Sep 06 2013
%e a(2) = 2^4 - 15*2 + 15 = 1;
%e a(4) = 4^4 - 15*4 + 15 = 211.
%t Table[(n^4 - 15 n + 15), {n, 1, 40}] (* _Vincenzo Librandi_, Sep 06 2013 *)
%t LinearRecurrence[{5,-10,10,-5,1},{1,1,51,211,565},40] (* _Harvey P. Dale_, Nov 23 2019 *)
%o (PARI) a(n) = n^4 - 15*n + 15; \\ _Michel Marcus_, Sep 05 2013
%o (Magma) [n^4 - 15*n + 15: n in [1..40]]; // _Vincenzo Librandi_, Sep 06 2013
%K nonn,easy
%O 1,3
%A Andras Erszegi (erszegi.andras(AT)chello.hu), May 14 2005
%E Definition clarified by _Ralf Stephan_, Nov 18 2010.
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