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 A121208 #4 Feb 16 2025 08:33:02 %S A121208 1,2,3,4,5,6,7,8,10,11,12,13,14,16,17,18,20,21,22,24,26,28,30,31,32, %T A121208 36,38,40,42,43,44,46,48,50,52,54,57,58,60,61,62,66,68,70,72,73,74,78, %U A121208 80,82,84,88,90,96,98,100,102,104,106,108,110,111,112,114,121,122,126,127 %N A121208 Cyclotomic polynomials evaluated at prime number abscissae. %C A121208 Contains as subsets: all A006093 which are Phi_1(p), all A008864 which are Phi_2(p), all A060800 which are Phi_3(p), all A066872 which are Phi_4(p) and all A119959 which are Phi_6(p). %H A121208 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CyclotomicPolynomial.html">Cyclotomic Polynomials</a>. %F A121208 a(n) = Phi_j(p), p in A000040, j=1,2,3,4... %e A121208 Contains 50, which is the fourth cyclotomic polynomial evaluated at the prime 7, 50=Phi_4(7). %Y A121208 Cf. A000040, A006093, A008864, A060800, A066872, A119959. %K A121208 nonn %O A121208 1,2 %A A121208 _R. J. Mathar_, Aug 20 2006