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 A235539 #8 Apr 25 2016 12:00:16 %S A235539 1,3,2,9,6,4,26,17,11,7,5,-21,-38,-49,-56,13,8,29,67,116,172,31,18,10, %T A235539 -19,-86,-202,-374,15,-16,-34,-44,-25,61,263,637,27,12,28,62,106,131, %U A235539 70,-193,-830,81,54,42,14,-48,-154,-285,-355,-162,668,22,-59,-113 %N A235539 Table with A235538 as first row, and k-th difference of A235538 as (k+1)-th row, read by antidiagonals. %C A235539 All terms are distinct in absolute value. %H A235539 Paul Tek, <a href="/A235539/b235539.txt">Table of n, a(n) for n = 1..5050</a> %H A235539 Paul Tek, <a href="/A235539/a235539.txt">PERL program for this sequence</a> %F A235539 T(1,n) = A235538(k) for any k>0. %F A235539 T(n+1,k) = T(n,k+1) - T(n,k) for any n>0 and k>0. %e A235539 The table begins: %e A235539 +---+---+---+---+---+ %e A235539 | 1 | 3 | 9 | 26| 5 | ... %e A235539 +-+-+-+-+-+-+-+-+-+-+ %e A235539 | 2 | 6 | 17|-21| ... %e A235539 +-+-+-+-+-+-+-+-+ %e A235539 | 4 | 11|-38| ... %e A235539 +-+-+-+-+-+-+ %e A235539 | 7 |-49| ... %e A235539 +-+-+-+-+ %e A235539 |-56| ... %e A235539 +---+ %o A235539 (Perl) See Link section. %Y A235539 Cf. A235538. %K A235539 sign,tabl %O A235539 1,2 %A A235539 _Paul Tek_, Jan 12 2014