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Numbers m such that (6*m)^5 is a sum of a twin prime pair.
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%I #4 Feb 05 2018 15:21:05

%S 16,44,84,135,161,631,849,880,1035,1086,1721,1815,2155,2704,2871,2975,

%T 3011,3159,3220,3365,3390,3669,3996,4075,4704,4761,5025,5090,5299,

%U 5585,5640,5970,6314,6606,7035,7785,8104,8129,8610,9116,9665,9966,10249

%N Numbers m such that (6*m)^5 is a sum of a twin prime pair.

%C The twin prime pairs are characterized in A173255.

%C No such m has least significant digit (LSD) e = 2 or 7 because a = (6 * e)^5/2 - 1, representing the smaller of the twin primes, would get LSD 5.

%C No such m has LSD e = 3 or 8, because a+2 = (6 * e)^5/2 + 1, representing the larger prime, would get LSD 5.

%C The primes in this sequence here are a(6) = 631 = prime(115), a(11) = 1721 = prime(268),

%C a(17) = 3011 = prime(432), a(49) = 10859 = prime(1320),...

%e p = (6 * 16)^5/2 - 1 = 4076863487 = A000040(193435931); p+2 = A000040(193435932), so a(1) = 16.

%e p = (6 * 44)^5/2 - 1 = 641194278911 = A000040(24524572848); p+2 = A000040(24524572849), so a(2) = 44.

%e p = (6 * 84)^5/2 - 1 = 16260080320511 = A000040(553382827197); p+2 = A000040(553382827198), so a(3) = 84.

%Y Cf. A001359, A061308, A069496, A172271, A172494, A173255

%K hard,nonn

%O 1,1

%A Ulrich Krug (leuchtfeuer37(AT)gmx.de), Feb 21 2010