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A137291 Numbers n such that p(n)^2-2 is prime where p(n) is the n-th prime. 1
1, 2, 3, 4, 6, 8, 10, 12, 14, 15, 18, 20, 24, 27, 28, 31, 32, 34, 40, 43, 47, 48, 51, 52, 55, 62, 65, 68, 72, 82, 86, 87, 91, 94, 99, 100, 104, 107, 111, 119, 123, 128, 129, 130, 132, 133, 134, 135, 139, 141, 150, 152, 170, 172, 177, 180, 182, 191, 200, 202, 209, 211 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

a(n)=A049084(A049002(n)). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 09 2008

EXAMPLE

n=24 : p(24)*p(24)-2=89*89-2=7919 is prime, n=24 belongs to the sequence.

CROSSREFS

Cf. A000040.

Sequence in context: A064377 A175495 A034884 * A032954 A158023 A004271

Adjacent sequences:  A137288 A137289 A137290 * A137292 A137293 A137294

KEYWORD

easy,nonn

AUTHOR

Ctibor O. Zizka (ctibor.zizka(AT)seznam.cz), Apr 05 2008

EXTENSIONS

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 09 2008

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Last modified February 15 14:02 EST 2012. Contains 205811 sequences.