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%I #20 Oct 15 2017 01:13:42
%S 11,31,61,151,181,211,331,541,631,691,751,811,991,1051,1201,1381,1531,
%T 1741,1831,1861,2161,2281,2311,2731,2851,3001,3061,3301,3361,3541,
%U 3631,3691,3931,4051,4111,4261,4591,4831,4951,5101,5431,5581,5641,5851,6151
%N Primes p such that (p+4)/5 is also prime.
%C Equivalently: Mother primes of order 2. For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180.
%H Vincenzo Librandi, <a href="/A136061/b136061.txt">Table of n, a(n) for n = 1..1000</a>
%t n = 2; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a
%t Select[Prime[Range[400]], PrimeQ[(# + 4) / 5]&] (* _Vincenzo Librandi_, Apr 14 2013 *)
%o (PARI) {forprime(p=1,1e4/*default(primelimit)*/, p%5-1 & next; isprime(p\5+1) & print1(p","))} \\ _M. F. Hasler_, Feb 26 2012
%o (GAP) A136061:=Filtered(Filtered([1..10^6],IsPrime),p->IsPrime((p+4)/5)); # _Muniru A Asiru_, Oct 10 2017
%Y Cf. A088878, A091180, A136019, A136020, A136062, A136063, A136064, A136065, A136066, A136067, A136068, A136069, A136070.
%K nonn,easy
%O 1,1
%A _Artur Jasinski_, Dec 12 2007
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