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%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