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 A131875 A000012 * A131844. 2
 1, 5, 4, 12, 5, 7, 22, 6, 8, 10, 35, 7, 9, 11, 13, 51, 8, 10, 12, 14, 16, 70, 9, 11, 13, 15, 17, 19, 92, 10, 12, 14, 16, 18, 20, 22, 117, 11, 13, 15, 17, 19, 21, 23, 25, 145, 12, 14, 16, 18, 20, 22, 24, 26, 28 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Left column = pentagonal numbers, A000326: (1, 5, 12, 22,...). Row sums = A001106: (1, 9, 24, 46, 75, 111,...). LINKS FORMULA A000012 * A131844 as infinite lower triangular matrices. EXAMPLE First few rows of the triangle are: 1; 5, 4; 12, 5, 7; 22, 6, 8, 10; 35, 7, 9, 11, 13; 51, 8, 10, 12, 14, 16; 70, 9, 11, 13, 15, 17, 19; 92, 10, 12, 14, 16, 18, 20, 22; ... CROSSREFS Cf. A131844, A001106, A000326. Sequence in context: A262902 A215332 A298779 * A095871 A284551 A316671 Adjacent sequences:  A131872 A131873 A131874 * A131876 A131877 A131878 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Jul 22 2007 STATUS approved

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Last modified April 18 03:59 EDT 2021. Contains 343072 sequences. (Running on oeis4.)