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%I #22 Sep 07 2013 14:24:26
%S 1,5,11,13,17,19,23,25,29,37,41,43,47,53,55,59,61,65,67,71,73,79,83,
%T 85,89,95,97,101,103,107,109,113,115,121,125,131,137,139,143,145,149,
%U 151,157,163,167,169,173,179,181,185,187,191,193,197,199,205,209
%N Numbers having no divisors d > 1 such that d + 1 are prime powers.
%C A141197(a(n)) = A049073(a(n)) = 1.
%C Contains all primes except for 2 and Mersenne primes A000668. - _Jon Perry_, Nov 11 2012
%C A composite number is in the sequence iff all its factors are. - _Jon Perry_, Nov 11 2012
%H Reinhard Zumkeller, <a href="/A185208/b185208.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[210], Select[Divisors[#] // Rest, PrimeNu[# + 1] == 1 &] == {} &] (* _Jean-François Alcover_, Aug 17 2013 *)
%o (Haskell)
%o a185208 n = a185208_list !! (n-1)
%o a185208_list = filter ((== 1) . a141197) [1..]
%Y Cf. A000961, A010055, A027750.
%Y Cf. A000668.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Nov 01 2012
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