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 A143427 a(n)=least prime == -1 mod 6 such that q(n)*(q(n)+a(n))-1 is prime with q(i)=i-th prime == 1 mod 6. 4
 5, 5, 11, 11, 5, 5, 11, 23, 5, 11, 17, 41, 23, 5, 11, 17, 29, 17, 17, 11, 47, 41, 11, 11, 41, 11, 29, 41, 5, 11, 29, 17, 11, 5, 47, 17, 17, 53, 11, 5, 17, 17, 47, 29, 11, 23, 11, 5, 17, 5, 17, 29, 11, 17, 29, 11, 17, 5, 11, 17, 5, 17, 17, 29, 17, 17, 5, 23, 23, 11, 113, 17, 113, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Pierre CAMI, Table of n, a(n) for n = 1..10000 EXAMPLE q(1)=7, 7*(7+5)-1=83 prime, 5 prime == -1 mod 6 so a(1)=5 q(2)=13, 13*(13+5)-1=233 prime, so a(2)=5 q(3)=19, 19*(19+5)-1=455 composite 19*(19+11)-1=569 prime, 11 prime == -1 mod 6 so a(3)=11 CROSSREFS Cf. A143428, A143429, A143430. Sequence in context: A130889 A184827 A058610 * A287996 A239355 A218121 Adjacent sequences: A143424 A143425 A143426 * A143428 A143429 A143430 KEYWORD nonn AUTHOR Pierre CAMI, Aug 14 2008 STATUS approved

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Last modified September 26 21:54 EDT 2023. Contains 365668 sequences. (Running on oeis4.)