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Triangle read by rows, M*Q, where M = an infinite lower triangular matrix with powers of 3 prefaced by a 1 in every row: (1, 1, 3, 9, 27, ...) and Q = a matrix with A006012 prefaced by a 1 as the main diagonal and the rest zeros.
1

%I #4 Feb 08 2022 23:24:28

%S 1,1,1,3,1,2,9,3,2,6,27,9,6,6,20,81,27,18,18,20,68,243,81,54,54,60,68,

%T 232,729,243,162,162,180,204,232,792,2187,729,486,486,540,612,696,792,

%U 2704,6561,2187,1458,1458,1620,1836,2088,2376,2704,9232

%N Triangle read by rows, M*Q, where M = an infinite lower triangular matrix with powers of 3 prefaced by a 1 in every row: (1, 1, 3, 9, 27, ...) and Q = a matrix with A006012 prefaced by a 1 as the main diagonal and the rest zeros.

%C Eigentriangle, row sums = A006012

%C Row sums = A006012: (1, 2, 6, 20, 68, 232, ...).

%C Sum of n-th row terms = rightmost term of next row.

%e First few rows of the triangle:

%e 1;

%e 1, 1;

%e 3, 1, 2;

%e 9, 3, 2, 6;

%e 27, 9, 6, 6, 20;

%e 81, 27, 18, 18, 20, 68;

%e 243, 81, 54, 54, 60, 68, 232;

%e 729, 243, 162, 162, 180, 204, 232, 792;

%e 2187, 729, 846, 486, 540, 612, 696, 792, 2704;

%e ...

%e Row 3 = (9, 3, 2, 6) = termwise products of (9, 3, 1, 1) and (1, 1, 2, 6).

%Y Cf. A006012.

%K eigen,nonn,tabl

%O 0,4

%A _Gary W. Adamson_, Nov 30 2008