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 A140648 #12 Jul 21 2017 06:52:38 %S A140648 1,2,0,4,1,0,8,2,0,1,16,4,1,0,2,32,8,2,0,1,4,64,16,4,1,0,2,8,128,32,8, %T A140648 2,0,1,4,16,256,64,16,4,1,0,2,8,32,512,128,32,8,2,0,1,4,16,64 %N A140648 Triangle T(n,m) which can create A140642 without help of Jacobsthal numbers. %C A140648 This triangle T(.,.) provides the additional terms if A140642 is constructed with a Pascal-type recurrence: A140642(n+1,m+1) = A140642(n,m) + A140642(n,m+1) + T(n,m+1). %C A140648 Note almost odd palindromes (of squares) followed by their double. %C A140648 Examples: 40=16+20+4, 42=20+21+1, 43=21+22+0, 44=22+24+2. %F A140648 Southeast diagonals based on A131577 (which is also in A140531). First preceded with 1, 0. Second with 2, 1, 0. Tends towards even palindromes, second part being A131577. Verticals: A000079, A131577, (0, A131577), ... . %e A140648 Triangle begins: %e A140648 1; %e A140648 2, 0; %e A140648 4, 1, 0; %e A140648 8, 2, 0, 1; %e A140648 16, 4, 1, 0, 2; %e A140648 32, 8, 2, 0, 1, 4; %e A140648 64, 16, 4, 1, 0, 2, 8; %e A140648 128, 32, 8, 2, 0, 1, 4, 16; %Y A140648 Cf. A083329 (row sums). %K A140648 nonn,tabl,uned %O A140648 0,2 %A A140648 _Paul Curtz_, Jul 09 2008