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A092519 Smallest prime a(n) such that a(n)+6n, a(n)+12n and a(n)+18n are also primes. 0
5, 5, 5, 59, 7, 31, 5, 5, 5, 11, 31, 7, 23, 5, 11, 5, 7, 23, 79, 29, 5, 5, 73, 29, 7, 41, 107, 43, 19, 59, 11, 37, 13, 79, 13, 11, 17, 43, 359, 23, 31, 5, 53, 19, 47, 181, 137, 23, 59, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(1) starts sequence A023271.
LINKS
EXAMPLE
a(5) = 7: 7+6(5) = 7+30 = 37 which is prime. 7+12(5) = 7+60 = 67 which is prime. 7+18(5) = 7+90 = 97 which is prime.
MATHEMATICA
Module[{nn=100, prs}, prs=Prime[Range[nn]]; Table[SelectFirst[prs, AllTrue[ #+6*Range[3]*n, PrimeQ]&], {n, nn/2}]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Dec 22 2018 *)
CROSSREFS
Sequence in context: A216876 A019162 A024951 * A198585 A224093 A193555
KEYWORD
nonn
AUTHOR
Ray G. Opao, Apr 06 2004
STATUS
approved

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Last modified May 7 13:58 EDT 2024. Contains 372309 sequences. (Running on oeis4.)