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 A020518 #20 Sep 16 2024 14:27:02 %S A020518 1,11,205,3641,61681,1016801,16519105,266354561,4278255361, %T A020518 68585520641,1098438933505,17583600302081,281406274007041, %U A020518 4503049938657281,72053196259835905,1152886321308467201,18446462603027742721,295145653396718878721,4722348468539854946305 %N A020518 10th cyclotomic polynomial evaluated at powers of 2. %H A020518 Colin Barker, <a href="/A020518/b020518.txt">Table of n, a(n) for n = 0..830</a> %H A020518 Quynh Nguyen, Jean Pedersen, and Hien T. Vu, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Pedersen/pedersen2.html">New Integer Sequences Arising From 3-Period Folding Numbers</a>, Vol. 19 (2016), Article 16.3.1. %H A020518 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (31,-310,1240,-1984,1024). %F A020518 G.f.: -(704*x^4-544*x^3+174*x^2-20*x+1) / ((x-1)*(2*x-1)*(4*x-1)*(8*x-1)*(16*x-1)). - _Colin Barker_, Feb 14 2015 %F A020518 a(n) = 1-2^n+4^n-8^n+16^n. - _Colin Barker_, Feb 15 2015 %F A020518 a(n) = A060884(A000079(n)). - _Michel Marcus_, Apr 06 2016 %p A020518 with(numtheory,cyclotomic):seq(cyclotomic(10,2^i),i=0..24); %t A020518 Cyclotomic[10, 2^Range[0, 20]] (* _Paolo Xausa_, Sep 16 2024 *) %o A020518 (PARI) a(n) = polcyclo(10, 2^n) \\ _Colin Barker_, Feb 14 2015 %Y A020518 Cf. A000079, A060884. %K A020518 nonn,easy %O A020518 0,2 %A A020518 _Simon Plouffe_ %E A020518 More terms from _Colin Barker_, Feb 14 2015