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A208456 Numbers n such that prime(n) <= 2^(prime(n+1)-prime(n)) < prime(n+1). 0
1, 2, 6, 18, 172, 6542, 2874398515 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Next term is approximately 1.386 * 10^43. [Charles R Greathouse IV, Feb 26 2012]

LINKS

Table of n, a(n) for n=1..7.

PROG

(PARI) for(k=1, log(default(primelimit))\log(2), p=precprime(2^k); q=nextprime(2^k+1); t=2^(q-p); if(p<=t&&q>t, print1(primepi(p)", "))) \\ Charles R Greathouse IV, Feb 26 2012

CROSSREFS

Cf. A206482, A208151.

Sequence in context: A308549 A212653 A323104 * A056743 A064535 A240643

Adjacent sequences:  A208453 A208454 A208455 * A208457 A208458 A208459

KEYWORD

nonn

AUTHOR

Gerasimov Sergey, Feb 26 2012

EXTENSIONS

a(4) corrected, a(6)-a(7) added by Charles R Greathouse IV, Feb 26 2012

STATUS

approved

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Last modified July 29 22:26 EDT 2021. Contains 346346 sequences. (Running on oeis4.)