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%I #5 Oct 31 2013 17:43:55
%S 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,
%T 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,
%U 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
%N Smallest number m such that prime(n)+2*prime(m) is a prime.
%C a(A114229(n)) = n for n >=1 and a(m) <> n for m < A114229(n). - _Reinhard Zumkeller_, Oct 31 2013
%H Reinhard Zumkeller, <a href="/A114228/b114228.txt">Table of n, a(n) for n = 2..10000</a>
%e prime(2)=3, 3+2*prime(1)=7 is prime, so a(2)=1;
%e prime(3)=5, 5+2*prime(2)=11 is prime, so a(3)=2;
%e ...
%e prime(20)=71, 71+2*prime(6)=97 is prime, so a(20)=6.
%t Table[p1 = Prime[n1]; n2 = 1; p2 = 2; While[ cp = p1 + 2*p2; ! PrimeQ[cp], n2++; p2 = Prime[n2]]; n2, {n1, 2, 201}]
%o (Haskell)
%o a114228 n = head [m | m <- [1..],
%o a010051 (a000040 n + 2 * a000040 m) == 1]
%o -- _Reinhard Zumkeller_, Oct 31 2013
%Y Cf. A114227.
%Y Cf. A010051, A000040.
%K easy,nonn
%O 2,2
%A _Lei Zhou_, Nov 18 2005
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