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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.

A162507 Triangle read by rows, finite differences of an array generated by an infinite product (Cf. A162506).

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%I A162507 #5 Sep 28 2016 06:38:50
%S A162507 1,2,1,2,3,1,4,3,4,1,4,9,4,5,1,6,12,12,5,6,1,6,18,24,15,6,7,1,8,24,36,
%T A162507 30,18,7,8,1,8,33,60,60,36,21,8,9,1,10,39,88,95,72,42,24,9,10,1,10,51,
%U A162507 124,160,138,84,48,27,10,11
%N A162507 Triangle read by rows, finite differences of an array generated by an infinite product (Cf. A162506).
%C A162507 Row sums = A162506 starting (1, 3, 6, 12, 23, 42, 77,...).
%F A162507 Given the infinite product and array shown in A162506, we have
%F A162507 a = [1,1,1,...], b = [1,0,2,0,2,0,2,...], c = [1,0,0,3,0,0,3,0,0,3,...];
%F A162507 The array is a, a*b, a*b*c,... Finite differences of array columns = rows of the triangle, deleting the first "1".
%e A162507 The array =
%e A162507 1,...1,...1,...1,...1,...; = a
%e A162507 1,...1,...3,...3,...5,...; = a*b
%e A162507 1,...1,...3,...6,...8,...; = a*b*c
%e A162507 1,...1,...3,...6,..12,...; = a*b*c*d
%e A162507 ...
%e A162507 taking finite differences from the top, then discarding the first "1",
%e A162507 we obtain triangle A162507:
%e A162507 1;
%e A162507 1, 2;
%e A162507 1, 2, 3;
%e A162507 1, 4, 3, 4;
%e A162507 1, 4, 9, 4, 5;
%e A162507 1, 6, 12, 12, 5, 6;
%e A162507 1, 6, 18, 24, 15, 6, 7;
%e A162507 1, 8, 24, 36, 30, 18, 7, 8;
%e A162507 1, 8, 33, 60, 60, 36, 21, 8, 9;
%e A162507 1, 10, 39, 88, 95, 72, 42, 24, 9, 10;
%e A162507 1, 10, 51, 124, 160, 138, 84, 48, 27, 10, 11;
%e A162507 ...
%Y A162507 Cf. A162506.
%K A162507 nonn,tabl
%O A162507 2,2
%A A162507 _Gary W. Adamson_, Jul 04 2009