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 A253648 #17 Aug 13 2020 14:02:28 %S A253648 89,91,107,117,119,121,125,127,137,141,143,151,154,155,157,159,161, %T A253648 163,167,170,171,173,175,178,179,181,182,185,187,189,190,191,193,195, %U A253648 196,197,199,201,202,203,205,206,207,209,211,213,215,217,218,221,224,225,226,227,229,233,234,235,236,237,238,239,241,242,243,244 %N A253648 Numbers of Hamiltonian cycles that require a graph with at least 9 vertices. %C A253648 Includes all numbers beyond 2520, starting from a(2290) = 2521 on, cf. formula. The first 2521 - 232 = 2289 terms contain the numbers in the interval [0, 2520] with 232 numbers missing, the largest being 2520. %H A253648 Erich Friedman, <a href="https://erich-friedman.github.io/mathmagic/0912.html">Math Magic</a> (September 2012) %F A253648 a(n) = n + 231 for n > 2289. %Y A253648 Cf. A244511, A305190. %K A253648 nonn %O A253648 1,1 %A A253648 _M. F. Hasler_, Jan 18 2015