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%I #7 Aug 26 2015 20:48:02
%S 1,1,24,720,2520,120960,259459200,1357171200,4929724800,
%T 42608389824000,11912739135897600,59907396092544000,
%U 20458385028297216000,7926428532945162240000,4693751193479184764928000,328774885640356760904499200000,12797917159224592605450240000
%N Product of composite numbers among next n numbers.
%C Conjecture: There are finitely many numbers such that a(n)is not == 0 (mod a(n-1). (Also mentioned in A093455.)
%C Product of all composite numbers between n*(n-1)/2+1 and n*(n+1)/2 (including boundaries). - _Stefan Steinerberger_, Apr 02 2006
%e a(5) = 12*14*15 = 2520.
%t Table[a := Range[n*(n - 1)/2 + 1, n*(n + 1)/2]; b := Select[a, Not[PrimeQ[ # ]] &]; Product[b[[i]], {i, 1, Length[b]}], {n, 1, 20}] (* _Stefan Steinerberger_, Apr 02 2006 *)
%Y Cf. A093455.
%K nonn,less
%O 1,3
%A _Amarnath Murthy_, Apr 03 2004
%E More terms from _Stefan Steinerberger_, Apr 02 2006
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