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%I #14 Jul 30 2022 09:37:09
%S 1,2,11,5,3,29,101,113,41,271,7,13,239,613,73,137,37,8291,9091,157637,
%T 313,21649,9901,2733970560857,53,79,229,4649,31,13001,17,19,6529,
%U 664193,6781,52579,1111111111111111111
%N a(1) = 1, then the smallest prime divisor of A065447(n) not included earlier.
%C Conjecture: Every prime is a member and this is a rearrangement of the noncomposite numbers.
%C Proof of conjecture: primes 2=a(1) and 5=a(3) are terms, while any other prime divides infinitely many numbers of the form A002275([(n+1)/2]) = (10^[(n+1)/2]-1)/9, which in turn divide A065447(n). Thus every prime will sooner or later appear as a(n). - _Max Alekseyev_, Jul 03 2019
%e a(6) = 29; smallest prime divisor of 100111000011111000000 not included earlier is 29. The prime divisors are 2, 3, 5, 29, 37, 97 and 106872959.
%Y Cf. A002275, A065447.
%K base,more,nonn
%O 1,2
%A _Amarnath Murthy_, Sep 13 2003
%E More terms from _David Wasserman_, Jun 06 2005
%E Offset corrected by _Max Alekseyev_, Jul 03 2019
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