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 A128140 A128132 * A004736. 1
 1, 3, 2, 7, 5, 3, 13, 10, 7, 4, 21, 17, 13, 9, 5, 31, 26, 21, 16, 11, 6, 43, 37, 31, 25, 19, 13, 7, 57, 50, 43, 36, 29, 22, 15, 8, 73, 65, 57, 49, 41, 33, 25, 17, 9, 91, 82, 73, 64, 55, 46, 37, 28, 19, 10 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums = A006003, starting (1, 5, 15, 34, 65, 111,...). Left border = A002061: (1, 3, 7, 13, 21, 31, 43,...) A128139 = A004736 * A128132 LINKS FORMULA A128132 * A004736 as infinite lower triangular matrices. EXAMPLE First few rows of the triangle are: 1; 3, 2; 7, 5, 3; 13, 10, 7, 4; 21, 17, 13, 9, 5; 31, 26, 21, 16, 11, 6; 43, 37, 31, 25, 19, 13, 7; ... CROSSREFS Cf. A128132, A004736, A006003, A004006, A128139. Sequence in context: A075627 A281825 A011384 * A213579 A137225 A213777 Adjacent sequences:  A128137 A128138 A128139 * A128141 A128142 A128143 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Feb 16 2007 STATUS approved

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Last modified November 30 06:28 EST 2021. Contains 349419 sequences. (Running on oeis4.)