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A111199
Numbers k such that 4k + 9 is prime.
6
1, 2, 5, 7, 8, 11, 13, 16, 20, 22, 23, 25, 26, 32, 35, 37, 41, 43, 46, 47, 55, 56, 58, 62, 65, 67, 68, 71, 76, 77, 82, 85, 86, 91, 95, 97, 98, 100, 103, 106, 110, 112, 113, 125, 128, 133, 137, 140, 142, 146, 148, 151, 152, 158, 161, 163, 166, 167, 173, 175, 181, 187
OFFSET
1,2
LINKS
FORMULA
a(n) = A005098(n+1) - 2. - R. J. Mathar, Sep 23 2009
EXAMPLE
For k=98, 4*k + 9 = 401 (prime).
PROG
(PARI) is(n)=isprime(4*n+9) \\ Charles R Greathouse IV, Feb 20 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Parthasarathy Nambi, Oct 24 2005
EXTENSIONS
More terms from R. J. Mathar, Sep 23 2009
STATUS
approved