A067267 Numbers n such that n, 10*n+1, 10*n+3, 10*n+7 and 10*n+9 are all primes.

19, 6949, 10111, 15727, 20149, 24799, 26041, 26881, 29587, 29947, 40213, 41203, 44257, 46747, 47701, 49057, 50023, 51061, 55921, 66109, 66643, 73939, 76819, 79579, 95947, 106501, 110083, 111781, 112213, 114679

Offset: 1

Author

Sudipta Das (juitech(AT)vsnl.net), Feb 21 2002

Keywords

• nonn

Comments

All terms == 1 (mod 6). - Robert Israel, Jan 22 2018

Examples

			a(1)=19 because 191, 193, 197 and 199 are all prime.
		

Links

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

Crossrefs

Cf. A007811.

Programs

Maple

select(t -> andmap(isprime, [t,10*t+1,10*t+3,10*t+7,10*t+9]), [seq(i,i=1..2*10^5,6)]); # Robert Israel, Jan 22 2018

Mathematica

okQ[n_]:=Module[{n10=10n},And@@PrimeQ[{n10+1,n10+3,n10+7,n10+9}]]
Select[Prime[Range[20000]],okQ] (* Harvey P. Dale, Dec 13 2010 *)
Select[Prime[Range[11000]],AllTrue[10#+{1,3,7,9},PrimeQ]&] (* Harvey P. Dale, Feb 23 2022 *)