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 A143254 Triangle read by rows, T(n,k) = (4n-3)*(4k-3); 1<=k<=n. 2
 1, 5, 25, 9, 45, 81, 13, 65, 117, 169, 17, 85, 153, 221, 289, 21, 105, 189, 273, 357, 441, 25, 125, 225, 325, 425, 525, 625, 29, 145, 261, 377, 493, 609, 725, 841, 33, 165, 297, 429, 561, 693, 825, 957, 1089, 37, 185, 333, 481, 629, 777, 925, 1073, 1221, 1369 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums = A100147: (1, 30, 135, 364, 765,...). LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 FORMULA 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;...) EXAMPLE First few rows of the triangle = 1; 5, 25; 9, 45, 81; 13, 65, 117, 169; 17, 85, 153, 221, 289; 21, 105, 189, 273, 357, 441; ... T(5,3) = 153 = (4n-3)*(4k-3) = 17*9 MATHEMATICA Flatten[Table[(4 n - 3) (4 k - 3), {n, 10}, {k, n}]] (* Harvey P. Dale, Feb 28 2015 *) CROSSREFS Cf. A016813, A100147. Sequence in context: A070386 A050084 A070379 * A070385 A070378 A070384 Adjacent sequences:  A143251 A143252 A143253 * A143255 A143256 A143257 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Aug 02 2008 STATUS approved

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Last modified October 16 03:34 EDT 2019. Contains 328040 sequences. (Running on oeis4.)