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 A171239 Triangle read by rows extracted from convolution product (1,2,3,...) * A002865: (1,1,2,2,4,4,7,8,...) 2
 1, 1, 2, 2, 2, 3, 2, 4, 3, 4, 4, 4, 6, 4, 5, 4, 8, 6, 8, 5, 6, 7, 8, 12, 8, 10, 6, 7, 8, 14, 12, 16, 10, 12, 7, 8, 8, 14, 12, 16, 10, 12, 7, 8, 12, 16, 21, 16, 20, 12, 14, 8, 9, 14, 24, 24, 28, 20, 24, 14, 10, 9, 10 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Row sums = A058682 starting (1, 3, 7, 13, 23, 37, 58, 87,...). LINKS FORMULA Triangle read by rows, ascending diagonals of an array formed by the product of (1,2,3,...) and (1,1,2,2,4,4,7,8,12,...). EXAMPLE The triangle = upward sloping diagonals of multiplication table: . 1,..2,..3,..4,..5,..6,..7,... 1,..2,..3,..4,..5,..6,..7,... 2,..4,..6,..8,.10,.12,.14,... 2,..4,..6,..8,.10,.12,.14,... ... First few rows of the triangle = . 1; 1, 2; 2, 2, 3; 2, 4, 3, 4; 4, 4, 6, 4, 5; 4, 8, 6, 8, 5, 6; 7, 8, 12, 8, 10, 6, 7; 8, 14, 12, 16, 10, 12, 7, 8; 12, 16, 21, 16, 20, 12, 14, 8, 9; 14, 24, 24, 28, 20, 24, 14, 10, 9, 10; 21, 28, 36, 32, 35, 24, 28, 16, 18, 10, 11; 24, 42, 42, 48, 40, 42, 28, 32, 18, 20, 11, 12; 34, 48, 63, 56, 60, 48, 49, 32, 36, 20, 22, 12, 13; 41, 68, 72, 84, 70, 72, 56, 56, 36, 40, 22, 24, 13, 14; ... CROSSREFS Cf. A002865, A058682 Sequence in context: A125749 A014085 A248891 * A029210 A321909 A035433 Adjacent sequences:  A171236 A171237 A171238 * A171240 A171241 A171242 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Dec 05 2009 STATUS approved

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Last modified March 21 01:18 EDT 2019. Contains 321356 sequences. (Running on oeis4.)