cp's OEIS Frontend

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

%I A067267 #15 Jul 16 2022 11:43:56
%S A067267 19,6949,10111,15727,20149,24799,26041,26881,29587,29947,40213,41203,
%T A067267 44257,46747,47701,49057,50023,51061,55921,66109,66643,73939,76819,
%U A067267 79579,95947,106501,110083,111781,112213,114679
%N A067267 Numbers n such that n, 10*n+1, 10*n+3, 10*n+7 and 10*n+9 are all primes.
%C A067267 All terms == 1 (mod 6). - _Robert Israel_, Jan 22 2018
%H A067267 Robert Israel, <a href="/A067267/b067267.txt">Table of n, a(n) for n = 1..10000</a>
%e A067267 a(1)=19 because 191, 193, 197 and 199 are all prime.
%p A067267 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
%t A067267 okQ[n_]:=Module[{n10=10n},And@@PrimeQ[{n10+1,n10+3,n10+7,n10+9}]]
%t A067267 Select[Prime[Range[20000]],okQ] (* _Harvey P. Dale_, Dec 13 2010 *)
%t A067267 Select[Prime[Range[11000]],AllTrue[10#+{1,3,7,9},PrimeQ]&] (* _Harvey P. Dale_, Feb 23 2022 *)
%Y A067267 Cf. A007811.
%K A067267 nonn
%O A067267 1,1
%A A067267 Sudipta Das (juitech(AT)vsnl.net), Feb 21 2002