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A071700 Product of twin primes of form (4*k+3,4*(k+1)+1), k>=0.

%I A071700 #14 Dec 12 2016 14:11:35
%S A071700 15,143,3599,5183,11663,32399,36863,51983,57599,97343,121103,176399,
%T A071700 186623,359999,435599,685583,1040399,1065023,1192463,1327103,1742399,
%U A071700 2039183,2108303,2214143,2585663,2624399,2782223
%N A071700 Product of twin primes of form (4*k+3,4*(k+1)+1), k>=0.
%H A071700 Reinhard Zumkeller, <a href="/A071700/b071700.txt">Table of n, a(n) for n = 1..10000</a>
%F A071700 a(n) >> n^2 log^4 n. - _Charles R Greathouse IV_, Jul 03 2013
%o A071700 (PARI) for(k=0,1e3,if(isprime(4*k+3)&&isprime(4*k+5),print1(16*k^2+32*k +15", "))) \\ _Charles R Greathouse IV_, Jul 03 2013
%o A071700 (PARI) is(n)=my(k=sqrtint(n\16)); n==16*k^2+32*k+15 && isprime(4*k+3) && isprime(4*k+5) \\ _Charles R Greathouse IV_, Jul 03 2013
%o A071700 (PARI) is(n)=my(t); n%16==15 && issquare(n+1,&t) && isprime(t-1) && isprime(t+1) \\ _Charles R Greathouse IV_, Dec 12 2016
%o A071700 (PARI) list(lim)=my(v=List(),p=3); forprime(q=5,sqrtint(1+lim\1)+1, if(q-p==2 && p%4==3, listput(v,p*q)); p=q); Vec(v) \\ _Charles R Greathouse IV_, Dec 12 2016
%o A071700 (Haskell)
%o A071700 a071700 n = a071700_list !! (n-1)
%o A071700 a071700_list = [x * y | x <- [3, 7 ..], a010051' x == 1,
%o A071700                         let y = x + 2, a010051' y == 1]
%o A071700 -- _Reinhard Zumkeller_, Aug 05 2014
%Y A071700 Subsequence of A037074, A071700 and of A182140.
%Y A071700 Cf. A071697, a(n) = A071698(n)*A071699(n).
%K A071700 nonn
%O A071700 1,1
%A A071700 _Reinhard Zumkeller_, Jun 04 2002