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%I #12 Mar 06 2022 08:34:52

%S 1,2,1,2,1,1,2,1,2,1,2,1,2,1,1,2,1,2,1,2,1,2,1,2,1,2,1,1,2,1,2,1,2,1,

%T 2,1,2,1,2,1,2,1,2,1,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,1,2,1,

%U 2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,1

%N A000012 * A133080.

%C Row sums = A032766, congruent to {0,1} (mod 3): (1, 3, 4, 6, 7, 9, 10, ...).

%H G. C. Greubel, <a href="/A133083/b133083.txt">Table of n, a(n) for the first 50 rows, flattened</a>

%F A000012 * A133080 as infinite lower triangular matrices.

%e First few rows of the triangle:

%e 1;

%e 2, 1;

%e 2, 1, 1;

%e 2, 1, 2, 1;

%e 2, 1, 2, 1, 1;

%e 2, 1, 2, 1, 2, 1;

%e ...

%t T[n_, k_] := If[k == n, 1, 1 + (1 - (-1)^k)/2 ]; Table[T[n, k], {n, 1, 10}, {k, 1, n}] (* _G. C. Greubel_, Oct 21 2017 *)

%o (PARI) for(n=1,10, for(k=1,n, print1(if(k==n, 1, 1 + (1-(-1)^k)/2), ", "))) \\ _G. C. Greubel_, Oct 21 2017

%Y Cf. A133080, A000012, A032766.

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, Sep 08 2007