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A163624
Numbers n such that 120n+1 is prime.
4
2, 5, 10, 11, 15, 18, 19, 21, 25, 26, 28, 35, 37, 38, 40, 44, 46, 47, 49, 51, 53, 54, 57, 58, 61, 63, 64, 68, 71, 72, 73, 75, 77, 80, 81, 86, 93, 102, 105, 106, 107, 112, 114, 116, 119, 120, 126, 127, 128, 130, 138, 141, 142, 145, 148, 149, 151, 154, 159, 162, 164, 165
OFFSET
1,1
LINKS
FORMULA
a(n) = (A163623(n)-1)/120.
MATHEMATICA
Select[Range[200], PrimeQ[120 # + 1] &] (* Harvey P. Dale, May 29 2013 *)
PROG
(Magma) [n: n in [0..250]|IsPrime(120*n+1)]; // Vincenzo Librandi, Dec 13 2010
(PARI) is(n)=isprime(120*n+1) \\ Charles R Greathouse IV, Feb 20 2017
CROSSREFS
Cf. A163623.
Sequence in context: A175324 A056704 A230408 * A353356 A363890 A257031
KEYWORD
nonn,easy
AUTHOR
Zak Seidov, Aug 01 2009
STATUS
approved