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A225724 Smallest prime q such that 2*prime(n)*q^prime(n)-1 is also prime. 1
2, 5, 43, 1409, 19, 107, 31, 653, 521, 1033, 661, 479, 787, 2063, 1307, 5477, 1471, 823, 1163, 1489, 6991, 9437, 1019, 6073, 17, 2089, 9413, 79, 3137, 12781, 13049, 3803, 10789, 3, 1321, 61, 7, 1187, 1733, 7151, 1327, 26111, 487, 3011, 31, 9343, 89653, 15377, 283, 21929 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Pierre CAMI, Table of n, a(n) for n = 2..250

PROG

( PFGW & SCRIPTIFY )

SCRIPT

DIM n, 1

DIM k

DIM q

DIM pp

DIMS t

OPENFILEOUT myfile, a(n).txt

LABEL a

SET n, n+1

IF n>250 THEN END

SET k, 0

LABEL b

SET k, k+1

SET q, p(k)

SETS t, %d, %d\,; n; q

SET pp, 2*p(n)*q^p(n)-1

PRP pp, t

IF ISPRP THEN GOTO c

GOTO b

LABEL c

WRITE myfile, t

GOTO a

CROSSREFS

Cf. A225403.

Sequence in context: A215170 A286871 A027730 * A333734 A163115 A221682

Adjacent sequences:  A225721 A225722 A225723 * A225725 A225726 A225727

KEYWORD

nonn

AUTHOR

Pierre CAMI, May 13 2013

STATUS

approved

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Last modified January 27 15:07 EST 2022. Contains 350607 sequences. (Running on oeis4.)