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A072744 Difference between the members of a pair of primes (p, q) with p < q and such that, for some integer k, (p+q)/2 = 2^k and p > 2^(k-1).

%I A072744 #11 Jan 24 2022 04:34:10
%S A072744 2,6,6,30,18,6,90,78,42,234,186,150,114,54,30,498,462,330,258,162,102,
%T A072744 90,18,894,846,810,594,546,534,510,426,294,210,54,30,1902,1722,1710,
%U A072744 1662,1578,1542,1482,1458,1362,1278,1230,1218,1122,990,858,822,702,522
%N A072744 Difference between the members of a pair of primes (p, q) with p < q and such that, for some integer k, (p+q)/2 = 2^k and p > 2^(k-1).
%F A072744 a(n) = A072743(n) - A072742(n).
%o A072744 (PARI) listkd(k) = {my(list = List()); forprime(p=2^(k-1)+1, 2^k, my(q=2^(k+1)-p); if ((q>p) && isprime(q), listput(list, q-p));); Vec(list);}
%o A072744 upto(k) = {my(list = List()); for (i=1, k, my(klist = listkd(i)); if (#klist, for (j=1, #klist, listput(list, klist[j])));); Vec(list);}
%o A072744 upto(11) \\ _Michel Marcus_, Jan 22 2022
%Y A072744 Cf. A072742, A072743, A072745.
%K A072744 nonn
%O A072744 1,1
%A A072744 _Reinhard Zumkeller_, Jul 08 2002
%E A072744 Name edited by _Michel Marcus_, Jan 22 2022