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Triangle read by rows, T(n,k) = (4n-3)*(4k-3); 1<=k<=n.
2

%I #4 Feb 28 2015 13:45:07

%S 1,5,25,9,45,81,13,65,117,169,17,85,153,221,289,21,105,189,273,357,

%T 441,25,125,225,325,425,525,625,29,145,261,377,493,609,725,841,33,165,

%U 297,429,561,693,825,957,1089,37,185,333,481,629,777,925,1073,1221,1369

%N Triangle read by rows, T(n,k) = (4n-3)*(4k-3); 1<=k<=n.

%C Row sums = A100147: (1, 30, 135, 364, 765,...).

%H Harvey P. Dale, <a href="/A143254/b143254.txt">Table of n, a(n) for n = 1..1000</a>

%F Triangle read by rows, T(n,k) = (4n-3)*(4k-3); 1<=k<=n, where (4k-3) = A016813: (1, 5, 9, 13, 17,...). Let X = an infinite lower triangular matrix with (1, 5, 9, 13,...) in the main diagonal and the rest zeros. The triangle = X * A000012 * X, where A000012 = an infinite lower triangular matrix with all 1's: (1; 1,1; 1,1,1;...)

%e First few rows of the triangle =

%e 1;

%e 5, 25;

%e 9, 45, 81;

%e 13, 65, 117, 169;

%e 17, 85, 153, 221, 289;

%e 21, 105, 189, 273, 357, 441;

%e ...

%e T(5,3) = 153 = (4n-3)*(4k-3) = 17*9

%t Flatten[Table[(4 n - 3) (4 k - 3), {n, 10}, {k, n}]] (* _Harvey P. Dale_, Feb 28 2015 *)

%Y Cf. A016813, A100147.

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, Aug 02 2008