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A340770 Indices k of prime numbers such that prime(k)-2 and prime(k)^2-2 are both prime numbers. 1
3, 4, 6, 8, 14, 18, 27, 34, 65, 82, 99, 141, 172, 177, 191, 202, 216, 226, 319, 333, 337, 445, 470, 476, 496, 552, 559, 564, 578, 602, 637, 672, 829, 850, 863, 871, 949, 1005, 1065, 1075, 1190, 1199, 1231, 1239, 1306, 1329, 1446, 1450, 1529, 1619, 1635, 1643 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence is a subsequence of A107770.

LINKS

François Marques, Table of n, a(n) for n = 1..10000

EXAMPLE

6 is in the sequence since prime(6)=13 and 13-2=11 and 13^2-2=167 are both prime numbers.

PROG

(PARI) lista(n) = {my(l=List, k=1); while(#l<n, k++; if(isprime(prime(k)-2) && isprime(prime(k)^2-2), listput(l, k))); return(l)};

CROSSREFS

Cf. A107770, A292201.

Sequence in context: A280250 A004713 A050475 * A242870 A025073 A325432

Adjacent sequences:  A340765 A340768 A340769 * A340771 A340772 A340773

KEYWORD

nonn,easy

AUTHOR

François Marques, Jan 20 2021

STATUS

approved

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Last modified April 18 14:40 EDT 2021. Contains 343088 sequences. (Running on oeis4.)