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A237414 Primes p with p^2 - 2 and prime(p)^2 - 2 both prime. 3
2, 3, 43, 47, 107, 139, 191, 211, 223, 239, 293, 313, 337, 541, 743, 757, 863, 1013, 1153, 1231, 1619, 2113, 2137, 2287, 2297, 2423, 2543, 2729, 2749, 2897, 3079, 3089, 3313, 3863, 3947, 4241, 4271, 4583, 4649, 4993, 5581, 6571, 6637, 6911, 7547, 8629, 8849, 8867, 9049, 9661 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

According to the conjecture in A237413, this sequence should have infinitely many terms.

LINKS

Zhi-Wei Sun, Table of n, a(n) for n = 1..10000

Z.-W. Sun, Problems on combinatorial properties of primes, arXiv:1402.6641, 2014

EXAMPLE

a(1) = 2 since 2^2 - 2 = 2 and prime(2)^2 - 2 = 3^2 - 2 = 7 are both prime.

MATHEMATICA

p[n_]:=PrimeQ[n^2-2]

n=0; Do[If[p[Prime[k]]&&p[Prime[Prime[k]]], n=n+1; Print[n, " ", Prime[k]]], {k, 1, 1000}]

CROSSREFS

Cf. A000040, A049002, A062326, A230502, A237413.

Sequence in context: A126018 A257467 A255092 * A051099 A162712 A182217

Adjacent sequences:  A237411 A237412 A237413 * A237415 A237416 A237417

KEYWORD

nonn

AUTHOR

Zhi-Wei Sun, Feb 07 2014

STATUS

approved

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Last modified February 26 17:04 EST 2021. Contains 341632 sequences. (Running on oeis4.)