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 A038506 #3 Dec 05 2013 19:54:47 %S A038506 1,2,3,4,5,6,7,8,9,2,3,4,5,6,7,8,9,10,11,5,6,7,8,9,10,11,12,13,14,8,9, %T A038506 10,11,12,13,14,15,16,17,10,11,12,13,14,15,16,17,18,19,13,14,15,16,17, %U A038506 18,19,20,21,22,16,17,18,19,20,21,22,23,24,25,19,20,21,22,23,24,25,26 %N A038506 Floor of decimal expansion of n read as if it were "base e". %C A038506 Define e-basing of a decimal number as f(a) = a, f(ab) = Floor[a*e + b], f(abc) = Floor[ a*e^2 +b*e + c], etc. and generalize, where a,b,c are the digits. e =2.71828182845904523536028747135266... %e A038506 a(135) = floor(1*e^2 + 3*e + 5) = floor(20.543901584307785933311289874633) = 20. %K A038506 base,nonn %O A038506 1,2 %A A038506 _Amarnath Murthy_, Nov 14 2002 %E A038506 More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Mar 23 2003