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%I #9 Jul 11 2015 10:35:27
%S 97,32920473601,1448500838401,65182537728001,
%T 1491301685600774317670400000001,
%U 48235157779343672198731287466250036763794299837586774072944798728192000000000000000001
%N Primes of the form 1 + product of the first n 3-almost primes A014612.
%C 3-almost prime analog of primorial primes A005234 (primes p such that 1 + product of primes up to p is prime) as indexed by A014545 (n such that n-th Euclid number (A006862(n)) = 1 + (Product of first n primes) is prime). In that sense, this sequence is indexed by (2, 8, 9, 10, 19, ...).
%F {a(n)} = {1 + Prod[from i = 1 to n] A014612(i)} INTERSECTION {A000040}.
%e a(1) = 97 = 96 + 1 = 1 + (8 * 12) = 1 + A014612(1)*A014612(2) = 1 more than the product of the first 2 of the 3-almost primes and is prime.
%e a(2) = 32920473601 = 1 + (8 * 12 * 18 * 20 * 27 * 28 * 30 * 42) = 1 more than the product of the first 8 of the 3-almost primes and is prime.
%e a(3) = 1 more than the product of the first 9 of the 3-almost primes and is prime.
%e a(4) = 1 more than the product of the first 10 of the 3-almost primes and is prime.
%e a(5) = 1 more than the product of the first 19 of the 3-almost primes and is prime.
%t Select[Rest[FoldList[Times,1,Select[Range[250],PrimeOmega[#]==3&]]]+1,PrimeQ] (* _Harvey P. Dale_, Dec 21 2013 *)
%Y Cf. A000040, A001358, A014612, A002110, A005234, A014545, A112141.
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, Feb 13 2006
%E One more term (a(6)) from _Harvey P. Dale_, Dec 21 2013
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