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 A015918 #13 Apr 07 2017 18:29:27 %S A015918 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0, %T A015918 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, %U A015918 0,0,0,0,0,0,0,0,0,0,0,0,0 %N A015918 Inverse of 1909th cyclotomic polynomial. %C A015918 Periodic with period length 1909. - _Ray Chandler_, Apr 07 2017 %H A015918 Ray Chandler, <a href="/A015918/b015918.txt">Table of n, a(n) for n = 0..2000</a> %H A015918 <a href="/index/Rec#order_1804">Index entries for linear recurrences with constant coefficients</a>, order 1804. %H A015918 <a href="/index/Pol#poly_cyclo_inv">Index to sequences related to inverse of cyclotomic polynomials</a> %p A015918 with(numtheory,cyclotomic); c := n->series(1/cyclotomic(n,x),x,80); %o A015918 (PARI) Vec(1/polcyclo(1909)+O(x^99)) \\ _Charles R Greathouse IV_, Mar 24 2014 %K A015918 sign %O A015918 0,1 %A A015918 _Simon Plouffe_