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 A240239 #6 Apr 11 2014 15:11:00 %S A240239 1,1,3,2,1,1,2,1,1,3,2,1,1,9,1,1,3,1,1,1,9,3,1,6,1,1,1,1,1,1,1,1,3,1, %T A240239 2,1,1,1,30,3,2,3,39,1,1,1,6,3,34,1,1,2,1,1,1,1,1,3,1,9,1,1,1,2,1,37, %U A240239 3,9,6,1,8,1,1,2,1,3,2,10,1,1,11,19,3,1,1,1,1,2,1,1,7,1,47,3,3,1,1,2,1,1 %N A240239 a(n) is one-half of the integer approximated by A135952(n)/A240238(n). %C A240239 The integer approximation can be made exact by first adding 1 to A135952(n) where a(n) is odd, or subtracting 1 from A135952(n) where a(n) is even, before dividing by A240238(n). %C A240239 Conjecture: a(n) never ends with the digit 5. %H A240239 Hans Havermann, <a href="/A240239/b240239.txt">Table of n, a(n) for n = 1..5000</a> %H A240239 Hans Havermann, <a href="http://gladhoboexpress.blogspot.ca/2014/04/magic-multipliers.html">Magic multipliers</a> %e A240239 (A135952(1)+1)/A240238(1) = (37+1)/19 = 2, so a(1) is 2/2 = 1. %e A240239 (A135952(2)+1)/A240238(2) = (73+1)/37 = 2, so a(2) is 2/2 = 1. %e A240239 (A135952(3)+1)/A240238(3) = (113+1)/19 = 6, so a(3) is 6/2 = 3. %e A240239 (A135952(4)-1)/A240238(4) = (149-1)/37 = 4, so a(4) is 4/2 = 2. %Y A240239 Cf. A135952, A240238. %K A240239 nonn %O A240239 1,3 %A A240239 _Hans Havermann_, Apr 02 2014