login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A242979 Primes p such that p^3-2 and p^2-2 are both primes. 2
19, 37, 211, 727, 2287, 4507, 4951, 5857, 6217, 6337, 7237, 8329, 8629, 8941, 9127, 9319, 9721, 11467, 12109, 13411, 13831, 15331, 15661, 17029, 17971, 17989, 19489, 21169, 23431, 24439, 24907, 25849, 26161, 31387, 33151, 34039, 34897, 36451, 37441, 37879 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A062326 and A178251.

LINKS

K. D. Bajpai, Table of n, a(n) for n = 1..10000

EXAMPLE

19 is prime and appears in the sequence because [19^3-2 = 6857] and [19^2-2 = 359] are both primes.

37 is prime and appears in the sequence because [37^3-2 = 50651] and [37^2-2 = 1367] are both primes.

MAPLE

with(numtheory):A242979:= proc() local p; p:=ithprime(n); if isprime(p^3-2) and isprime(p^2-2)then RETURN (p); fi; end: seq( A242979 (), n=1..5000);

MATHEMATICA

c = 0; t=Prime[n]; Do[If[PrimeQ[t^3 - 2] && PrimeQ[t^2 - 2], c++; Print[c, "  ", t]], {n, 1, 3*10^6}];

CROSSREFS

Cf. A000040, A001248, A030078, A062326, A178251.

Sequence in context: A053685 A244111 A136063 * A244931 A111441 A144594

Adjacent sequences:  A242976 A242977 A242978 * A242980 A242981 A242982

KEYWORD

nonn

AUTHOR

K. D. Bajpai, May 28 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 28 06:42 EST 2021. Contains 349401 sequences. (Running on oeis4.)