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A107771
Numbers n such that 2*n + 5 and 5*n + 2 are primes.
2
0, 1, 3, 7, 9, 13, 19, 21, 27, 31, 33, 39, 51, 61, 63, 67, 73, 79, 93, 97, 109, 111, 117, 123, 129, 151, 171, 177, 181, 187, 189, 217, 219, 237, 243, 247, 259, 297, 313, 319, 321, 327, 339, 357, 369, 373, 403, 417, 427, 441, 453, 457, 471, 483, 489, 493, 523, 529
OFFSET
1,3
COMMENTS
Union of A089038 and A111223.
Except for the first, all terms == 1 or 3 (mod 6). - Robert Israel, Apr 02 2020
LINKS
MAPLE
select(n -> isprime(2*n+5) and isprime(5*n+2), [0, seq(i, i=1..1000, 2)]); # Robert Israel, Apr 02 2020
MATHEMATICA
Reap[Do[If[PrimeQ[2*n+5]&&PrimeQ[5*n+2], Sow[n]], {n, 0, 600}]][[2, 1]]
CROSSREFS
Sequence in context: A088649 A020498 A200567 * A364614 A215800 A103601
KEYWORD
nonn
AUTHOR
Zak Seidov, Mar 31 2006
STATUS
approved