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 A143269 Triangle read by rows, A127648 * A000012 * A130207, 1<=k<=n. 1
 1, 2, 2, 3, 3, 6, 4, 4, 8, 8, 5, 5, 10, 10, 20, 6, 6, 12, 12, 24, 12, 7, 7, 14, 14, 28, 14, 42, 8, 8, 16, 16, 32, 16, 48, 32, 9, 9, 18, 18, 36, 18, 54, 36, 54, 10, 10, 20, 20, 40, 20, 60, 40, 60, 40, 11, 11, 22, 22, 44, 22, 66, 44, 66, 44, 110 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums = A143270: (1, 4, 12, 24, 50, 72, 126, 176,...). LINKS FORMULA Triangle read by rows, A127648 * A000012 * A130207. T(n,k) = n*phi(k) EXAMPLE First few rows of the triangle = 1; 2, 2; 3, 3, 6; 4, 4, 8, 8; 5, 5, 10, 10, 20; 6, 6, 12, 12, 24, 12; 7, 7, 14, 1428, 14, 42; ... Row 5 = (5, 5, 10, 10, 20) = (5*1, 5*1, 5*2, 5*2, 5*4); where phi(k) = (1, 1, 2, 2, 4,...). CROSSREFS Cf. A000010, A143270. Sequence in context: A165122 A240505 A051715 * A036817 A239962 A175175 Adjacent sequences:  A143266 A143267 A143268 * A143270 A143271 A143272 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Aug 03 2008 STATUS approved

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Last modified January 18 14:07 EST 2021. Contains 340254 sequences. (Running on oeis4.)