A225724 Smallest prime q such that 2*prime(n)*q^prime(n)-1 is also prime.

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

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