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 A173306 #6 Nov 19 2022 12:33:07 %S A173306 1,1,1,1,2,1,2,2,1,3,3,1,4,5,2,5,7,3,6,10,5,1,8,14,7,1,10,19,11,2,12, %T A173306 26,15,3,15,35,22,5,18,46,30,7,22,60,42,11,27,78,56,15,32,10,76,22,1, %U A173306 38,128,100,30,1,46,162,133,42,2,54,204,173,56,3 %N A173306 Triangle read by rows, generated from an array of terms in powers of triangle A173305. %C A173306 Row sums = A000041, the partition numbers. %F A173306 Given triangle A173305 in which every column >0 = A000009 shifted down twice. %F A173306 We create an array in which n-th row = columns in (n-1)-th power of triangle %F A173306 A173305. Finite differences of successive columns of the array become row terms %F A173306 of A173306. %e A173306 Given triangle A173305, we create an array by extracting terms in powers of A173305: %e A173306 1, 1, 1, 2, 2, 3, .4, .5, .6, .8, 10, 12, 15,...; = column terms of A173305 %e A173306 1, 1, 2, 3, 4, 6, .9, 12, 16, 22, 29, 38, 50,...; = terms of A173305^2 %e A173306 1, 1, 2, 3, 5, 7, 11, 15, 21, 29, 40, 53, 72,...; = terms of A173305^3 %e A173306 1, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42, 56, 77,...; = terms of A173305^4 %e A173306 ... %e A173306 (rows quickly converge to A000041, the partition numbers). %e A173306 Taking finite difference terms from the top, we obtain the array: %e A173306 1, 1, 1, 2, 2, 3, .4, .5, .6,..8, 10, 12, 15,...; %e A173306 ......1, 1, 2, 3, .5, .7, 10, 14, 19, 26, 35,...; %e A173306 ............1, 1, .2, .3, .5, .7, 11, 15, 22,...; %e A173306 ...........................1, .1, .2, .3, .5,...; %e A173306 ... %e A173306 Finally, columns of the above array become rows of A173306: %e A173306 1; %e A173306 1; %e A173306 1, 1; %e A173306 2, 1; %e A173306 2, 2, 1; %e A173306 3, 3, 1; %e A173306 4, 5, 2; %e A173306 5, 7, 3; %e A173306 6, 10, 5, 1; %e A173306 8, 14, 7, 1; %e A173306 10, 19, 11, 2; %e A173306 12, 26, 15, 3; %e A173306 15, 35, 22, 5; %e A173306 18, 46, 30, 7; %e A173306 22, 60, 42, 11; %e A173306 27, 78, 56, 15; %e A173306 32, 100, 76, 22, 1; %e A173306 38, 128, 100, 30, 1; %e A173306 46, 162, 133, 42, 2; %e A173306 54, 204, 173, 56, 3; %e A173306 ... %Y A173306 Cf. A000009, A000041, A173305. %K A173306 nonn,tabf %O A173306 0,5 %A A173306 _Gary W. Adamson_, Feb 15 2010