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 A109915 Product of all composite numbers k such that n
 1, 1, 4, 1, 6, 1, 720, 90, 10, 1, 12, 1, 3360, 240, 16, 1, 18, 1, 9240, 462, 22, 1, 11793600, 491400, 19656, 756, 28, 1, 30, 1, 45239040, 1413720, 42840, 1260, 36, 1, 59280, 1560, 40, 1, 42, 1, 91080, 2070, 46, 1, 311875200, 6497400, 132600, 2652 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS All terms that differ from 1 have the format A092435(i+1)/A092435(i). - R. J. Mathar, Aug 15 2007 LINKS EXAMPLE a(7) = 8*9*10 = 720. MAPLE A109915 := proc(n) local a, rm1, k; a := 1: rm1 := numtheory[pi](n) ; for k from n+1 to ithprime(rm1+1) do if not isprime(k) then a := a*k; fi; od: RETURN(a) ; end: seq(A109915(n), n=1..50) ; # R. J. Mathar, Aug 15 2007 CROSSREFS Cf. A109914. Sequence in context: A032220 A032145 A032050 * A334467 A255198 A202521 Adjacent sequences: A109912 A109913 A109914 * A109916 A109917 A109918 KEYWORD nonn AUTHOR Amarnath Murthy, Jul 16 2005 EXTENSIONS Corrected and extended by R. J. Mathar, Aug 15 2007 STATUS approved

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Last modified April 1 22:11 EDT 2023. Contains 361716 sequences. (Running on oeis4.)