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 A097284 #3 Mar 30 2012 18:57:05 %S A097284 1,3,2,5,7,4,9,11,8,6,13,15,17,12,10,19,21,23,18,16,14,25,27,29,31,24, %T A097284 22,20,33,35,37,39,32,30,28,26,41,43,45,47,49,40,38,36,34,51,53,55,57, %U A097284 59,50,48,46,44,42,61,63,65,67,69,71,60,58,56,54,52,73,75,77,79,81,83 %N A097284 Rectangular array T by antidiagonals: T(n,k) = rank of k-th n in A097283. %C A097284 As a sequence, this is a permutation of the natural numbers. %e A097284 Northwest corner: %e A097284 1 3 5 9 13 %e A097284 2 7 11 15 21 %e A097284 4 8 17 23 29 %e A097284 6 12 18 31 39 %Y A097284 Cf. A097283. %K A097284 nonn,tabl %O A097284 1,2 %A A097284 _Clark Kimberling_, Aug 05 2004