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 A138842 #8 Mar 14 2020 05:56:22 %S A138842 22,44,16,64,46,66,24,14,16,36,84,84,36,24,54,74,26,16,96,14,26,16,16, %T A138842 26,26,26,46,24,24,26,34,84,66,24,46,36,66,26,46,64,14,64,16,66,14,86, %U A138842 16 %N A138842 Concatenation of initial and final digits of n-th even superperfect number A061652(n). %C A138842 Also, concatenation of initial and final digits of n-th superperfect number A019279(n), if there are no odd superperfect numbers. %C A138842 Also, concatenation of A138124(n) and A138125(n). %Y A138842 Cf. A019279, A061652, A073729, A138124, A138125, A138838, A138840, A138841, A138843, A138844. %K A138842 nonn,base,more,less %O A138842 1,1 %A A138842 _Omar E. Pol_, Apr 02 2008 %E A138842 More terms from _Jinyuan Wang_, Mar 14 2020