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A104165
Sophie Germain type primes where 7*Prime[n]=2*Prime[m]+1.
0
17, 59, 101, 311, 353, 479, 521, 941, 983, 1109, 1361, 1571, 1613, 1823, 1949, 2243, 2663, 2789, 2999, 3083, 3251, 3671, 3881, 4133, 4259, 4931, 5939, 5981, 6569, 6653, 7283, 7451, 7829, 8039, 8081, 8543, 8669, 9173, 9551, 9719, 9803, 9929, 10139
OFFSET
1,1
FORMULA
a(n) = If (7*Prime[n]-1)/2 is prime, then a[m]=(7*Prime[n]-1)/2
MATHEMATICA
a = Delete[Union[Table[If [PrimeQ[(7*Prime[n] - 1)/2] == True, (7*Prime[n] - 1)/2, 0], {n, 1, 1000}]], 1]
CROSSREFS
Cf. Sophie Germain primes: A005384.
Sequence in context: A110092 A360155 A141896 * A031391 A176783 A086816
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Mar 10 2005
STATUS
approved