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 A195104 Smallest prime p such that p*t(n) +- 1 is a twin prime pair, where t(n)=A014574(n) is the n-th twin prime average. 1
 3, 2, 5, 11, 2, 11, 3, 29, 101, 199, 29, 7, 13, 11, 29, 71, 13, 3, 71, 101, 29, 43, 79, 5, 11, 11, 5, 29, 61, 2, 2, 11, 19, 11, 29, 5, 11, 7, 41, 19, 181, 19, 59, 5, 11, 7, 29, 11, 41, 179, 41, 13, 61, 181, 19, 241, 139, 331, 271, 3, 59, 5, 41, 89, 19, 2, 5, 131, 59, 5, 5, 509, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) = 2 for n in A158866. - Robert Israel, Mar 07 2021 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE a(4)=11 because 11*A014574(4) +- 1 = 11*18 +- 1 = 198 +- 1 is a twin prime pair, A014574(4) +- 1 = 18 +- 1 is also a twin prime pair, and 11 is prime. MAPLE A195104 := proc(n)     k := A014574(n) ;     for i from 1 do         p := ithprime(i) ;         if isprime(p*k-1) and isprime(p*k+1) then             return p;         end if;     end do: end proc: seq(A195104(n), n=1..60) ; # R. J. Mathar, Dec 16 2011 CROSSREFS Cf. A014574, A158866. Sequence in context: A209199 A215328 A107298 * A338879 A257905 A305878 Adjacent sequences:  A195101 A195102 A195103 * A195105 A195106 A195107 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Dec 16 2011 EXTENSIONS a(64) corrected by Robert Israel, Mar 07 2021 STATUS approved

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Last modified May 7 22:52 EDT 2021. Contains 343652 sequences. (Running on oeis4.)