

A114262


p is the smallest prime that is greater than prime(n) such that prime(n)+2*p is a prime.


7



5, 7, 11, 13, 17, 31, 41, 37, 37, 41, 47, 43, 47, 67, 73, 61, 83, 83, 79, 83, 89, 97, 97, 107, 103, 107, 151, 137, 127, 131, 139, 151, 191, 157, 179, 167, 173, 223, 199, 181, 191, 193, 197, 211, 227, 233, 227, 241, 257, 277, 307, 251, 313, 277, 283, 271, 293, 281
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OFFSET

2,1


LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 2..10000


EXAMPLE

n=2: prime[2]=3; 3+2*5=13 is prime, so a(2)=5;
n=3: prime[3]=5; 5+2*7=19 is prime, so a(3)=7;
...
n=7: prime[7]=17; 17+2*19=55 is not prime
17+2*23=63 is not prime
...
17+2*31=79 is prime, so a(7)=31.


MATHEMATICA

Table[p1 = Prime[n1]; n2 = 1; p2 = Prime[n1 + n2]; While[cp = p1 + 2* p2; ! PrimeQ[cp], n2++; p2 = Prime[n1 + n2]]; p2, {n1, 2, 201}]


PROG

(Haskell)
a114262 n = head [q  let (p:ps) = drop (n  1) a000040_list,
q < ps, a010051 (p + 2 * q) == 1]
 Reinhard Zumkeller, Oct 29 2013


CROSSREFS

Cf. A114227, A114230, A073703, A114235.
Cf. A000040, A010051.
Sequence in context: A132170 A106309 A227576 * A255229 A230217 A007529
Adjacent sequences: A114259 A114260 A114261 * A114263 A114264 A114265


KEYWORD

easy,nonn


AUTHOR

Lei Zhou, Nov 20 2005


EXTENSIONS

Edited definition to conform to OEIS style.  Reinhard Zumkeller, Oct 31 2013


STATUS

approved



