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 A185290 #16 May 11 2013 12:31:04 %S A185290 1,2,3,4,6,9,5,10,16,25,7,12,22,38,63,8,15,27,49,87,150,11,19,34,61, %T A185290 110,197,347,13,24,43,77,138,248,445,792,14,28,52,95,172,310,558,1003, %U A185290 1795,17,31,59,111,206,378,688,1246,2249,4044,18,35,66,125,236,442,820,1508,2754,5003,9047,20,39,74,140,265,501,943,1763 %N A185290 Lexicographically least permutation of the integers in a triangle satisfying T(n,k) + T(n+1,k) <= T(n+1,k+1). %C A185290 Apparently, T(n,k) ~ n*2^k as n grows. %H A185290 Paul Tek, <a href="/A185290/b185290.txt">Table of n, a(n) for n = 1..10000</a> %e A185290 The first rows are: %e A185290 [1] %e A185290 [2,3] %e A185290 [4,6,9] %e A185290 [5,10,16,25] %e A185290 For T(1,1), we choose the first integer not yet used: 1. %e A185290 For T(2,1), we choose the first integer not yet used: 2. %e A185290 For T(2,2), we choose the first integer >= T(1,1)+T(2,1) not yet used: 3. %e A185290 For T(3,1), we choose the first integer not yet used: 4. %e A185290 For T(3,2), we choose the first integer >= T(2,1)+T(3,1) not yet used: 6. %e A185290 For T(3,3), we choose the first integer >= T(2,2)+T(3,2) not yet used: 9. %e A185290 etc. %Y A185290 Cf. A035312. %K A185290 nonn,tabl %O A185290 1,2 %A A185290 _Paul Tek_, Apr 23 2013