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 A138480 #35 Mar 20 2025 10:36:10 %S A138480 1210,2020,21200,3211000,42101000,521001000,6210001000,72100001000, %T A138480 821000001000,9210000001000 %N A138480 Autobiographical numbers: the first digit specifies how many 0's in the number, the next digit specifies how many 1's, etc. This version is not limited to 10 digits. %D A138480 E. Angelini, "Jeux de suites", in Dossier Pour La Science, pp. 32-35, Volume 59 (Jeux math'), April/June 2008, Paris. %H A138480 Shyam Sunder Gupta, <a href="https://doi.org/10.1007/978-981-97-2465-9_22">On Some Special Numbers</a>, Exploring the Beauty of Fascinating Numbers, Springer (2025) Ch. 22, 527-565. %H A138480 Tanya Khovanova, <a href="https://www.youtube.com/watch?v=lRfdMiURV4s">Can you solve the Leonardo da Vinci riddle?</a>, TED-Ed YouTube channel. %e A138480 72100001000 has 7 digits equal to "0", 2 digits equal to "1", 1 digit each "2" and "7" and no other digits. %Y A138480 Autobiographical numbers up to 10 digits: A046043. Mutually-praising pairs: A138481 and A138482. %K A138480 base,fini,full,nonn %O A138480 1,1 %A A138480 _Martin Fuller_, Mar 20 2008