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 A143218 Triangle read by rows, A127775 * A000012 * A127775; 1<=k<=n. 0
 1, 3, 9, 5, 15, 25, 7, 21, 35, 49, 9, 27, 45, 63, 81, 11, 33, 55, 77, 99, 121, 13, 39, 65, 91, 117, 143, 169, 15, 45, 75, 105, 135, 165, 195, 225, 17, 51, 85, 119, 153, 187, 221, 255, 289, 19, 57, 95, 133, 171, 209, 247, 285, 323, 361, 21, 63, 105, 147, 189, 231, 273, 315 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums = A015237: (1, 12, 45, 112, 225, 396,...) LINKS FORMULA Triangle read by rows, A127775 * A000012 * A127775. T(n,k) = (2*n - 1) * (2*k - 1), 1<=k<=n. EXAMPLE First few rows of the triangle = 1; 3, 9; 5, 15, 25; 7, 21, 35, 49; 9, 27, 45, 63, 81; 11, 33, 55, 77, 99, 121; 13, 39, 65, 91, 117, 143, 169; ... T(5,3) = 45 = 9*5 = (2*5 - 1) * (2*3 - 1). CROSSREFS Cf. A005408, A127775, A015237. Sequence in context: A134001 A338350 A088898 * A262024 A252117 A103934 Adjacent sequences:  A143215 A143216 A143217 * A143219 A143220 A143221 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Jul 30 2008 STATUS approved

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Last modified May 10 00:35 EDT 2021. Contains 343747 sequences. (Running on oeis4.)