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 A178912 #5 Mar 31 2012 13:22:29 %S A178912 9,0,240,1380,4578,10794,19494,27912,32195,30085,22748,13820,6656, %T A178912 2486,695,137,17,1 %N A178912 Number of generalized mountain numbers (see A134853) with n digits. %C A178912 The total number of generalized mountain numbers is 173247. %e A178912 a(18) = 1 because there is exactly one generalized mountain number with 18 digits: 123456789876543210 %Y A178912 Cf. A134853, A134941, A135417 %K A178912 base,nonn,fini,full %O A178912 1,1 %A A178912 _Nathaniel Johnston_, Dec 29 2010