%I #12 Feb 20 2022 01:26:57
%S 1,0,1,2,0,1,0,2,0,1,2,0,2,0,1,0,2,0,2,0,1,2,0,2,0,2,0,1,0,2,0,2,0,2,
%T 0,1,2,0,2,0,2,0,2,0,1,0,2,0,2,0,2,0,2,0,1
%N A129686 * A128174.
%C Resulting triangle has (1, 0, 2, 0, 2, 0, 2, ...) in every column.
%C Row sums = A109613: (1, 1, 3, 3, 5, 5, ...).
%F A129686 * A128174 as infinite lower triangular matrices.
%e First few rows of the triangle:
%e 1;
%e 0, 1;
%e 2, 0, 1;
%e 0, 2, 0, 1;
%e 2, 0, 2, 0, 1;
%e ...
%t T[n_, k_] := If[k == n, 1, If[EvenQ[n + k], 2, 0]];
%t Table[T[n, k], {n, 1, 10}, {k, 1, n}] // Flatten (* _Jean-François Alcover_, Jul 10 2019 *)
%Y Cf. A129686, A128174, A109613.
%K nonn,tabl
%O 1,4
%A _Gary W. Adamson_, Apr 28 2007