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 A171095 Triangle read by rows: row n contains sequence S_n = [s(1), ..., s(n)] where s(1) is the least semiprime pq such that the recurrence s(i+1) = sum of two prime factors of s(i) generates a chain of exactly n semiprimes. 0
 4, 9, 6, 14, 9, 6, 33, 14, 9, 6, 62, 33, 14, 9, 6, 177, 62, 33, 14, 9, 6, 886, 445, 94, 49, 14, 9, 6, 2649, 886, 445, 94, 49, 14, 9, 6, 5294, 2649, 886, 445, 94, 49, 14, 9, 6, 68653, 5294, 2649, 886, 445, 94, 49, 14, 9, 6, 496966, 248485, 49702, 24853, 886 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE Triangle begins: 4 9, 6 14, 9, 6 33, 14, 9, 6 62, 33, 14, 9, 6 177, 62, 33, 14, 9, 6 886, 445, 94, 49, 14, 9, 6 2649, 886, 445, 94, 49, 14, 9, 6 5294, 2649, 886, 445, 94, 49, 14, 9, 6 68653, 5294, 2649, 886, 445, 94, 49, 14, 9, 6 496966, 248485, 49702, 24853, 886, 445, 94, 49, 14, 9, 6 1490889, 496966, 248485, 49702, 24853, 886, 445, 94, 49, 14, 9, 6 16896262, 8448133, 496966, 248485, 49702, 24853, 886, 445, 94, 49, 14, 9, 6 185858761, 16896262, 8448133, 496966, 248485, 49702, 24853, 886, 445, 94, 49, 14, 9, 6 ... CROSSREFS Sequence in context: A218072 A335306 A261023 * A075065 A141553 A095065 Adjacent sequences:  A171092 A171093 A171094 * A171096 A171097 A171098 KEYWORD nonn,tabl AUTHOR N. J. A. Sloane, Sep 23 2010, based on a posting to the Sequence Fans Mailing List by Hans Havermann, Sep 10 2010 STATUS approved

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Last modified June 21 19:59 EDT 2021. Contains 345365 sequences. (Running on oeis4.)