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Primes q of form q=10p+7, where p is also prime.
3

%I #13 Apr 24 2024 06:39:46

%S 37,137,197,317,617,677,797,977,1097,1277,1637,1997,2237,2297,2417,

%T 2777,2837,3137,3677,3797,4217,4337,4397,4637,4877,5237,5417,5477,

%U 5717,6197,6317,6737,6917,7517,7577,7877,8117,8237,8297,8537,8597,8837,9377

%N Primes q of form q=10p+7, where p is also prime.

%e 5417=541*10+7, 7 is concatenated to end of 541.

%t Select[(10#+7)&/@Prime[Range[200]],PrimeQ] (* _Harvey P. Dale_, Nov 20 2010 *)

%Y Cf. A005384, A005385. Subsequence of A030432.

%K nonn

%O 1,1

%A _Labos Elemer_, Jul 13 2000