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 A054076 #4 Mar 30 2012 18:57:01 %S A054076 1,2,3,6,4,5,9,7,10,8,15,13,11,14,12,20,18,16,21,19,17,26,24,22,27,25, %T A054076 23,28,33,31,36,29,34,32,30,35,41,39,44,37,42,40,45,38,43,50,55,48,53, %U A054076 46,51,49,54,47,52,60,65,58,63,56,61,66,59 %N A054076 Permutation of N: a(n)+C(k,2), where a=A054073 and k=Floor((1+sqrt(8n-3))/2). %e A054076 Referring to A054073, just add C(k,2) to the numbers in p(k); e.g. p(1)=1->(1); p(2)=(1,2)->(2,3); p(3)=(3,1,2)->(6,4,5). %K A054076 nonn %O A054076 1,2 %A A054076 _Clark Kimberling_