This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A121672 #32 Apr 09 2024 17:20:28 %S A121672 0,-4,-38,-12,404,1900,5646,13412,27688,51804,90050,147796,231612, %T A121672 349388,510454,725700,1007696,1370812,1831338,2407604,3120100,3991596, %U A121672 5047262,6314788,7824504,9609500,11705746,14152212,16990988,20267404,24030150 %N A121672 Real part of (n + i)^5. %C A121672 The companion sequence A121671 uses the operation (1 + n*i)^5. %H A121672 Vincenzo Librandi, <a href="/A121672/b121672.txt">Table of n, a(n) for n = 0..1000</a> %H A121672 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (6,-15,20,-15,6,-1). %F A121672 G.f.: -2*x*(2+7*x-78*x^2+7*x^3+2*x^4)/(1-x)^6. - _Bruno Berselli_, Mar 01 2012 %F A121672 a(n) = n*(n^4-10*n^2+5). - _Bruno Berselli_, Mar 01 2012 %F A121672 a(n) = (1+n^2)^(5/2)*sin(5*arctan(n)). - _Gerry Martens_, Apr 06 2024 %e A121672 a(4) = 404 since (4 + i)^5 = (404 + 1121i) where 1121 = A121671(4). %t A121672 Re[(Range[0,30]+I)^5] (* _Harvey P. Dale_, Mar 01 2012 *) %o A121672 (PARI) a(n) = real((n + I)^5); \\ _Michel Marcus_, Dec 19 2020 %Y A121672 Cf. A121671, A080663, A121670. %K A121672 sign,easy %O A121672 0,2 %A A121672 _Gary W. Adamson_, Aug 14 2006 %E A121672 Corrected and extended by _Harvey P. Dale_, Mar 01 2012