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A208149 Primes p(n) such that p(n) <= 2^(p(n+1) - p(n)). 2
2, 3, 7, 13, 23, 31, 47, 53, 61, 89, 113, 139, 181, 199, 211, 241, 283, 293, 317, 337, 409, 421, 467, 509, 523, 547, 577, 619, 631, 661, 691, 709, 773, 787, 797, 811, 829, 839, 863, 887, 919, 953, 997, 1021, 1069, 1129, 1201, 1237, 1259, 1307, 1327, 1381 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

EXAMPLE

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

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

MATHEMATICA

Select[Prime[Range[300]], # <= 2^(NextPrime[#] - #) &] (* T. D. Noe, Feb 28 2012 *)

PROG

(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

CROSSREFS

Cf. A001223.

Sequence in context: A332861 A182047 A291544 * A144104 A088175 A271827

Adjacent sequences: A208146 A208147 A208148 * A208150 A208151 A208152

KEYWORD

nonn

AUTHOR

Gerasimov Sergey, Feb 23 2012

STATUS

approved

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Last modified January 30 19:31 EST 2023. Contains 359947 sequences. (Running on oeis4.)