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 A097288 #2 Mar 30 2012 18:57:05 %S A097288 2,1,6,3,4,12,7,5,8,20,13,9,10,14,30,21,15,11,16,22,42,31,23,17,18,24, %T A097288 32,56,43,33,25,19,26,34,44,72,57,45,35,27,28,36,46,58,90,73,59,47,37, %U A097288 29,38,48,60,74,110,91,75,61,49,39,40,50,62,76,92,132,111,93,77,63,51 %N A097288 Rectangular array read by antidiagonals obtained from A097287 by deleting the zeros. %C A097288 As a sequence, this is a permutation of the natural numbers. Evens lie on or below the main diagonal; odds, above. The triangle formed by the evens is twice that of A066182. %e A097288 Northwest corner: %e A097288 2 1 3 7 13 %e A097288 6 4 5 9 15 %e A097288 12 8 10 11 17 %e A097288 20 14 16 18 19 %Y A097288 Cf. A097287. %K A097288 nonn,tabl %O A097288 1,1 %A A097288 _Clark Kimberling_, Aug 05 2004