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A208149 Primes p(n) such that p(n) <= 2^(p(n+1) - p(n)). 2

%I

%S 2,3,7,13,23,31,47,53,61,89,113,139,181,199,211,241,283,293,317,337,

%T 409,421,467,509,523,547,577,619,631,661,691,709,773,787,797,811,829,

%U 839,863,887,919,953,997,1021,1069,1129,1201,1237,1259,1307,1327,1381

%N Primes p(n) such that p(n) <= 2^(p(n+1) - p(n)).

%H Charles R Greathouse IV, <a href="/A208149/b208149.txt">Table of n, a(n) for n = 1..10000</a>

%e 2 is here because prime(1)=2^(prime(1+1)-prime(1)) or 2=2^(3-2);

%e 3 is here because prime(2)<2^(prime(2+1)-prime(2)) or 3<2^(5-3).

%t Select[Prime[Range[300]], # <= 2^(NextPrime[#] - #) &] (* _T. D. Noe_, Feb 28 2012 *)

%o (PARI) v=List();p=2;forprime(q=3,1e4,if(p<=2^(q-p),listput(v,p));p=q); Vec(v) \\ _Charles R Greathouse IV_, Aug 03 2012

%Y Cf. A001223.

%K nonn

%O 1,1

%A _Gerasimov Sergey_, Feb 23 2012

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Last modified March 29 20:41 EDT 2023. Contains 361599 sequences. (Running on oeis4.)