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 A143228 Triangle read by rows, T(n,k) = (p(n)*p(k)), where p(n) & p(k) = the number of partitions of n; 0<=k<=n. 1
 1, 1, 1, 2, 2, 4, 3, 3, 6, 9, 5, 5, 10, 15, 25, 7, 7, 1421, 35, 49, 11, 11, 22, 33, 55, 77, 121, 15, 15, 30, 45, 75, 105, 165, 225, 22, 22, 44, 66, 110, 154, 242, 330, 484, 30, 30, 60, 90, 150, 210, 330, 450, 660, 900, 42, 42, 84, 126, 210, 294, 462630, 924, 1260, 1764 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Left border = A000041. Row sums = A143229: (1, 2, 8, 21, 60, 133, 330, 675,...). LINKS FORMULA Triangle read by rows, T(n,k) = (p(n)*p(k)), where p(n) & p(k) = the number of partitions of n. Let X = the infinite lower triangular matrix with A000041 in the main diagonal and the rest zeros = A000041 * 0^(n-k); 0<=k<=n. The triangle = X * A000012 * X. EXAMPLE First few rows of the triangle = 1; 1, 1; 2, 2, 4; 3, 3, 6, 9; 5, 5, 10, 15, 25; 7, 7, 14, 21, 35, 49; 11, 11, 22, 33, 55, 77, 121; 15, 15, 30, 45, 75, 105, 165, 225; ... T(7,4) = 75 = p(7) * p(4) = 15 * 5. CROSSREFS Cf. A000041, A143229. Sequence in context: A212652 A205678 A128590 * A143211 A209755 A131052 Adjacent sequences:  A143225 A143226 A143227 * A143229 A143230 A143231 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Jul 31 2008 STATUS approved

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Last modified May 20 04:18 EDT 2013. Contains 225446 sequences.