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 A036565 #19 Aug 21 2025 08:35:50
%S A036565 1,2,7,4,14,49,8,28,98,343,16,56,196,686,2401,32,112,392,1372,4802,
%T A036565 16807,64,224,784,2744,9604,33614,117649,128,448,1568,5488,19208,
%U A036565 67228,235298,823543,256,896,3136,10976,38416,134456,470596,1647086,5764801
%N A036565 Triangle of numbers in which i-th row is {2^(i-j)*7^j, 0<=j<=i}; i >= 0.
%F A036565 G.f.: 1/((1 - 2*x)(1 - 7*x*y)). - _Ilya Gutkovskiy_, Jun 03 2017
%e A036565 The triangle begins as:
%e A036565 1;
%e A036565 2, 7;
%e A036565 4, 14, 49;
%e A036565 8, 28, 98, 343;
%e A036565 ...
%t A036565 row[n_] := Table[SeriesCoefficient[1/((1 - 2*x)(1 - 7*x*y)), {x, 0, i}, {y, 0, j}], {i, n, n}, {j, 0, n}]; Array[row,9,0]//Flatten (* _Stefano Spezia_, Aug 19 2025 *)
%Y A036565 Cf. A003591.
%Y A036565 Cf. A000079 (1st column), A000420 (diagonal), A016130 (row sums).
%K A036565 nonn,easy,tabl
%O A036565 0,2
%A A036565 _N. J. A. Sloane_