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A126608
Smallest odd prime q such that pq+2 is prime, where p is the n-th odd prime.
6
3, 3, 3, 7, 3, 3, 3, 3, 3, 5, 3, 61, 3, 7, 7, 3, 5, 5, 7, 5, 3, 3, 3, 3, 7, 3, 7, 5, 13, 3, 7, 13, 3, 3, 5, 5, 3, 3, 3, 43, 5, 19, 5, 3, 3, 29, 5, 3, 11, 3, 3, 17, 7, 3, 19, 3, 41, 11, 31, 17, 3, 41, 7, 3, 3, 5, 3, 13, 3, 3, 19, 3, 5, 23, 3, 13, 3, 19, 3, 3, 17, 7, 3, 3, 19, 13, 3, 7, 17, 7, 3, 5, 37, 3
OFFSET
1,1
MATHEMATICA
f[n_] := Block[{p = Prime[n + 1], k = 1, q}, While[q = Prime[k + 1]; ! PrimeQ[p*q + 2], k++ ]; q]; Table[f[n], {n, 95}] (* Ray Chandler, Feb 07 2007
CROSSREFS
Cf. A126609.
Sequence in context: A079988 A212091 A061021 * A088195 A131757 A214834
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Feb 06 2007
EXTENSIONS
Extended by Ray Chandler, Feb 07 2007
STATUS
approved