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 A195902 #24 Jun 05 2025 13:48:06 %S A195902 1,189949981,3031430341303,1139781083801879311,1414082803082804141, %T A195902 1444271276721724441,1966548318138456691,3457863858583687543, %U A195902 3516331046401336153,193361787181787163391,3876643622232322263466783 %N A195902 Palindromic centered 22-gonal numbers. %C A195902 a(12) > 10^26. - _Donovan Johnson_, Sep 27 2011 %H A195902 Terry Trotter, <a href="http://trottermath.net/polygonal-numbers/">Polygonal numbers</a> %F A195902 a(n) = A069173(A196494(n)). %K A195902 nonn,base %O A195902 1,2 %A A195902 _Kausthub Gudipati_, Sep 25 2011 %E A195902 a(8)-a(10) from _Giovanni Resta_, Sep 26 2011 %E A195902 a(11) from _Donovan Johnson_, Sep 27 2011