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%I #11 Jul 11 2015 11:27:28
%S 32,1536,110592,8847360,955514880,107017666560,12842119987200,
%T 2080423437926400,349511137571635200,61513960212607795200,
%U 11072512838269403136000,2214502567653880627200000,460616534072007170457600000,111929817779497742421196800000
%N Product of the first n 5-almost primes (A014614).
%C 5-almost prime analog of primorial (A002110). The semiprime analog of primorial is A112141. Equivalent for product of what A086047 is for sum. Bigomega(a(n)) = the number of not necessarily distinct prime factors of a(n) = A001222(a(n)) = A008587(n) = 5*n.
%F a(n) = Prod[i=1..n] A014614(i).
%e a(10) = 32 * 48 * 72 * 80 * 108 * 112 * 120 * 162 * 168 * 176 = 2^33 * 3^12 * 5^2 * 7^2 * 11 which has 50 prime factors with multiplicity.
%t Rest[FoldList[Times,1,Select[Range[200],PrimeOmega[#]==5&]]] (* _Harvey P. Dale_, Feb 07 2012 *)
%Y Cf. A001222, A002110, A008585, A014613, A008587, A086046, A086047, A112141, A114426.
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, Oct 19 2006
%E More terms from _Harvey P. Dale_, Feb 07 2012
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