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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 December 4 19:34 EST 2023. Contains 367563 sequences. (Running on oeis4.)