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A057665 Numbers n such that prime(n)+2^prime(n) is prime. 3
2, 3, 24, 66, 126 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(6) > 3002, since prime(3002) = 27479 (see comment by Ralf Stephan in A057663). - Michel Marcus, Dec 20 2013

These values correspond to indices ip = 2, 3, 9, 10, 11 where A052007(ip) is prime. - Michel Marcus, Dec 20 2013

LINKS

Table of n, a(n) for n=1..5.

FORMULA

a(n) = primepi(A057663(n)). - Michel Marcus, Dec 20 2013

MATHEMATICA

Select[Range[10^3], PrimeQ[# + 2^#] &@ Prime@ # &] (* Michael De Vlieger, Oct 26 2017 *)

PROG

(PARI) isok(n) = isprime(prime(n) + 2^prime(n)); \\ Michel Marcus, Dec 19 2013

CROSSREFS

Cf. A052007, A057663, A057664.

Sequence in context: A061355 A160618 A279335 * A157327 A009231 A012304

Adjacent sequences:  A057662 A057663 A057664 * A057666 A057667 A057668

KEYWORD

nonn,more,hard

AUTHOR

Labos Elemer, Oct 16 2000

EXTENSIONS

Name edited by Michel Marcus, Dec 19 2013

STATUS

approved

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Last modified January 16 21:37 EST 2019. Contains 319206 sequences. (Running on oeis4.)