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A128949 Smallest primes > 2^n that are twin prime members. 1
3, 5, 11, 17, 521, 1031, 65537, 8388617, 862718293348820473429344482784628181556388621521298319395315527975161, 56539106072908298546665520023773392506479484700019806659891398441363833147 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A prime is included only if it is both the smallest prime greater than 2^n and also the smaller of a twin-prime pair. - Harvey P. Dale, Aug 24 2013

LINKS

Table of n, a(n) for n=1..10.

FORMULA

a(n) = A014210(A128944(n)).

MATHEMATICA

Select[NextPrime[2^Range[250]], PrimeQ[#+2]&] (* Harvey P. Dale, Aug 24 2013 *)

PROG

(PARI) g(n, b)=for(x=1, n, y=nextprime(b^x); if(ispseudoprime(y+2), print1(y", ")))

CROSSREFS

Cf. Intersection of A014210 (Next prime after 2^n) and A001097 (Twin primes).

Sequence in context: A090952 A270778 A267030 * A070316 A298121 A244473

Adjacent sequences:  A128946 A128947 A128948 * A128950 A128951 A128952

KEYWORD

nonn

AUTHOR

Cino Hilliard, Apr 28 2007

EXTENSIONS

Edited by Ray Chandler, May 12 2007

One more term (a(10)) from Harvey P. Dale, Aug 24 2013

STATUS

approved

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Last modified February 17 21:35 EST 2020. Contains 332006 sequences. (Running on oeis4.)