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 A114228 Smallest number m such that prime(n)+2*prime(m) is a prime. 8
 1, 2, 1, 2, 1, 2, 1, 2, 4, 2, 1, 2, 1, 2, 2, 4, 2, 1, 6, 2, 1, 2, 4, 1, 2, 1, 2, 1, 4, 1, 2, 4, 3, 4, 2, 2, 1, 2, 2, 4, 3, 2, 1, 4, 7, 5, 1, 2, 1, 2, 8, 3, 2, 2, 2, 4, 2, 1, 6, 3, 4, 1, 2, 1, 4, 2, 3, 2, 1, 2, 4, 2, 2, 1, 2, 12, 1, 8, 3, 4, 3, 6, 2, 1, 2, 4, 1, 2, 1, 12, 11, 1, 14, 1, 2, 4, 6, 7, 2, 3, 2, 2, 8 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,2 COMMENTS a(A114229(n)) = n for n >=1 and a(m) <> n for m < A114229(n). - Reinhard Zumkeller, Oct 31 2013 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 2..10000 EXAMPLE prime(2)=3, 3+2*prime(1)=7 is prime, so a(2)=1; prime(3)=5, 5+2*prime(2)=11 is prime, so a(3)=2; ... prime(20)=71, 71+2*prime(6)=97 is prime, so a(20)=6. MATHEMATICA Table[p1 = Prime[n1]; n2 = 1; p2 = 2; While[ cp = p1 + 2*p2; ! PrimeQ[cp], n2++; p2 = Prime[n2]]; n2, {n1, 2, 201}] PROG (Haskell) a114228 n = head [m | m <- [1..],                       a010051 (a000040 n + 2 * a000040 m) == 1] -- Reinhard Zumkeller, Oct 31 2013 CROSSREFS Cf. A114227. Cf. A010051, A000040. Sequence in context: A030738 A341541 A330559 * A230287 A336336 A168580 Adjacent sequences:  A114225 A114226 A114227 * A114229 A114230 A114231 KEYWORD easy,nonn AUTHOR Lei Zhou, Nov 18 2005 STATUS approved

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Last modified June 25 00:34 EDT 2021. Contains 345445 sequences. (Running on oeis4.)