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%I #16 Sep 08 2022 08:45:40
%S 6,12,30,36,48,54,84,114,120,132,162,204,210,246,258,264,324,390,426,
%T 462,468,510,546,558,594,600,624,660,666,672,678,708,786,804,810,846,
%U 852,930,960,1002,1020,1056,1104,1128,1170,1176,1218,1254,1260,1272
%N Numbers n such that 5n-1 and 5n+1 are both prime.
%C a(n) is an integer multiple of 6. - _Alois P. Heinz_, Jan 04 2009
%H Vincenzo Librandi, <a href="/A153877/b153877.txt">Table of n, a(n) for n = 1..1000</a>
%e n=6, 5n-1=29, 5n+1=31; n=30, 5n-1=149, 5n+1=151.
%p a:= proc(n::posint) option remember; local m; if n=1 then 6 else for m from a(n-1)+6 by 6 while not (isprime(5*m-1) and isprime(5*m+1)) do od; m fi end: seq(a(n), n=1..100); # _Alois P. Heinz_, Jan 04 2009
%t Select[Range[0,100001],PrimeQ[5#-1]&& PrimeQ[5#+1]&] (* _Vincenzo Librandi_, Jul 31 2012 *)
%o (Magma) [ n: n in [0..2000] | IsPrime(5*n-1) and IsPrime(5*n+1)]; // _Vincenzo Librandi_, Jul 31 2012
%Y Cf. A153355, A153088.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Jan 03 2009
%E Corrected and extended by _Alois P. Heinz_ and _R. J. Mathar_, Jan 04 2009
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