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 A143956 Triangle read by rows, A000012 * A136521 * A000012; 1<=k<=n. 0
 1, 3, 2, 5, 4, 2, 7, 6, 4, 2, 9, 8, 6, 4, 2, 11, 10, 8, 6, 4, 2, 13, 12, 10, 8, 6, 4, 2, 15, 14, 12, 10, 8, 6, 4, 2, 17, 16, 14, 12, 10, 8, 6, 4, 2, 19, 18, 16, 14, 12, 10, 8, 6, 4, 2, 21, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums = A028387: (1, 5, 11, 19, 29, 41,...) LINKS Table of n, a(n) for n=1..66. FORMULA Triangle read by rows, A000012 * A136521 * A000012; 1<=k<=n. A136521 = an infinite lower triangular matrix with (1,2,2,2,...) in the main diagonal the rest zeros. EXAMPLE First few rows of the triangle = 1; 3, 2; 5, 4, 2; 7, 6, 4, 2; 9, 8, 6, 4, 2; 11, 10, 8, 6, 4, 2; 13, 12, 10, 8, 6, 4, 2; 15, 14, 12, 10, 8, 6, 4, 2; ... CROSSREFS Cf. A136521, A028387. Sequence in context: A363447 A371905 A371908 * A110661 A143124 A205400 Adjacent sequences: A143953 A143954 A143955 * A143957 A143958 A143959 KEYWORD nonn,tabl AUTHOR Gary W. Adamson & Roger L. Bagula, Aug 26 2008 STATUS approved

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Last modified April 17 13:32 EDT 2024. Contains 371764 sequences. (Running on oeis4.)