A240716 Both 1 + 6 n and 6 + 35 n are prime.

1, 5, 7, 13, 17, 23, 25, 35, 37, 55, 61, 91, 95, 101, 121, 131, 137, 143, 161, 175, 187, 221, 233, 245, 257, 271, 311, 335, 391, 395, 397, 443, 445, 451, 461, 475, 511, 527, 545, 557, 577, 583, 641, 653, 683, 685, 703, 737, 761, 773, 787, 797, 805

Offset: 1

Author

Robert Israel, Apr 10 2014

Keywords

• nonn

Comments

The consecutive integers 35 + 210 a(n) and 36 + 210 a(n) are both products of three primes (distinct if n > 1).

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A215217.

Programs

Magma

[n: n in [0..1000] | IsPrime(6*n+1) and IsPrime(35*n+6)]; // Vincenzo Librandi, Jul 01 2014

Maple

A240716 := select(t -> andmap(isprime,[1+6*t,6+35*t]),[$1..N]); # Robert Israel, Apr 10 2014

Mathematica

Select[Range[1000], PrimeQ[6 # + 1] && PrimeQ[35 # + 6] &] (* Vincenzo Librandi, Jul 01 2014 *)