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%I #8 Sep 15 2015 16:04:31
%S 5,11,13,19,23,37,43,47,61,67,73,79,103,151,157,163,191,193,211,223,
%T 271,277,283,313,331,367,383,397,421,457,463,487,523,541,547,607,613,
%U 631,661,673,691,733,751,757,787,823,877,907,991,997,1051,1087,1093
%N Odd primes p such that p+1 is a prime times a power of two.
%C Very similar to A192869; here p+1 = q*2^k, where q must be prime.
%H T. D. Noe, <a href="/A206581/b206581.txt">Table of n, a(n) for n = 1..1000</a>
%H Kevin Broughan and Zhou Qizhi, <a href="http://www.math.waikato.ac.nz/~kab/papers/flatandthin4.pdf">Flat primes and thin primes</a>, Bulletin of the Australian Mathematical Society 82:2 (2010), pp. 282-292.
%F a(n) >> n log^2 n is implicit in Broughan & Qizhi, see A192869. - _Charles R Greathouse IV_, Sep 15 2015
%t Select[Prime[Range[2, 1000]], PrimeQ[(#+1)/2^IntegerExponent[#+1, 2]] &]
%o (PARI) is(n)=isprime(n) && n>4 && isprime((n+1)>>valuation(n+1,2)) \\ _Charles R Greathouse IV_, Sep 15 2015
%Y Subsequence of A192869.
%K nonn
%O 1,1
%A _T. D. Noe_, Mar 07 2012
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