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 A132939 #9 Dec 30 2022 02:46:53 %S A132939 1,11,112,1124,11249,1124921,112492151,112492151127,112492151127323, %T A132939 112492151127323835,1124921511273238352188,11249215112732383521885798, %U A132939 1124921511273238352188579815511,112492151127323835218857981551141835 %N A132939 Concatenate Motzkin numbers (A001006). %Y A132939 Motzkin numbers: A001006. Cf. A007908, A019518, A059996. %K A132939 easy,nonn,base %O A132939 0,2 %A A132939 _Omar E. Pol_, Sep 12 2007 %E A132939 a(13) corrected by _Georg Fischer_, Dec 30 2022