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%I #9 Sep 08 2022 08:45:35
%S 7,47,127,167,367,487,607,647,727,887,967,1087,1327,1367,1447,1487,
%T 1567,1607,1847,2087,2207,2287,2447,2647,2687,2767,2887,2927,3167,
%U 3407,3527,3607,3727,3767,3847,3967,4007,4127,4327,4447,4567,4967,5087,5167,5407
%N Primes congruent to 7 mod 40.
%H Vincenzo Librandi, <a href="/A142185/b142185.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) ~ 16n log n. - _Charles R Greathouse IV_, Jul 03 2016
%t Select[Prime[Range[2000]],MemberQ[{7},Mod[#,40]]&] (* _Vincenzo Librandi_, Aug 20 2012 *)
%o (Magma) [p: p in PrimesUpTo(7000) | p mod 40 eq 7]; // _Vincenzo Librandi_, Aug 20 2012
%o (PARI) is(n)=isprime(n) && n%40==7 \\ _Charles R Greathouse IV_, Jul 03 2016
%Y Cf. A000040.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Jul 11 2008