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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.

A368435 Irregular triangular array T, read by rows: T(n,k) = number of sums |x-y|+|y-z| = 2n-2-k, where x,y,z are in {0,1,...,n}.

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%I A368435 #4 Dec 30 2023 23:41:33
%S A368435 1,2,4,2,2,4,10,8,3,2,4,8,16,18,12,4,2,4,8,12,24,28,26,16,5,2,4,8,12,
%T A368435 18,32,40,40,34,20,6,2,4,8,12,18,24,42,52,56,52,42,24,7,2,4,8,12,18,
%U A368435 24,32,52,66,72,72,64,50,28,8,2,4,8,12,18,24,32,40
%N A368435 Irregular triangular array T, read by rows: T(n,k) = number of sums |x-y|+|y-z|  = 2n-2-k, where x,y,z are in {0,1,...,n}.
%C A368435 Row n consists of 2n-1 positive integers having sum A000575(n) = n^3.
%e A368435 First eight rows:
%e A368435 1
%e A368435 2  4   2
%e A368435 2  4  10   8   3
%e A368435 2  4   8  16  18  12   4
%e A368435 2  4   8  12  24  28  26  16   5
%e A368435 2  4   8  12  18  32  40  40  34  20   6
%e A368435 2  4   8  12  18  24  42  52  56  52  42  24   7
%e A368435 2  4   8  12  18  24  32  52  66  72  72  64  50  28  8
%t A368435 t[n_] := t[n] = Tuples[Range[n], 3];
%t A368435 a[n_, k_] := Select[t[n], Abs[#[[1]] - #[[2]]] + Abs[#[[2]] - #[[3]]] == 2n-2-k &];
%t A368435 u = Table[Length[a[n, k]], {n, 1, 15}, {k, 0, 2 n - 2}];
%t A368435 Flatten[u]  (* sequence *)
%t A368435 Column[u]   (* array *)
%Y A368435 Cf. A000575, A007590 (limiting row), A368434, A368437.
%K A368435 nonn,tabf
%O A368435 1,2
%A A368435 _Clark Kimberling_, Dec 25 2023