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%I #12 Jan 13 2020 14:57:33
%S 1,3,2,2,2,3,170,46600,1901907,65157236,42083217792,2819475721641
%N a(1) = 1; for n > 1: a(n) = smallest number >1 such that product of any two or more successive terms - 1 is prime.
%e a(2) is not 2 since 1*2-1 = 1 is not prime, but 1*3-1 = 2 is prime, hence a(2) = 3.
%e a(6) is not 2 since 2*2*2*2-1 = 15 is not prime, but 2*3-1 = 5, 2*2*3-1 = 11, 2*2*2*3-1 = 23, 3*2*2*2*3-1 = 71 are all prime, hence a(6) = 3.
%Y Cf. A096100.
%K nonn,more
%O 1,2
%A _Amarnath Murthy_, Jun 24 2004
%E Edited and extended by _Klaus Brockhaus_, Jul 05 2004
%E a(10) from _Donovan Johnson_, Apr 22 2008
%E a(11)-a(12) from _Bert Dobbelaere_, Jan 13 2020
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