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Smallest b > n+2 such that n*b^n + 1 is a generalized Cullen prime with n > 1 and base b > n+2 or 0 if no such prime exists.
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%I #10 Nov 15 2017 04:52:01

%S 6,10,0,8,14,30,12,14,132,42,143,60,30,22,170,30,665,198,42,200,138,

%T 104,115,34,84,0,1740,54,403,130,150,134,58,72,111,778,204,174,1681,

%U 108,344,178,585,86,7426,904,133,234,63,1376,114,108

%N Smallest b > n+2 such that n*b^n + 1 is a generalized Cullen prime with n > 1 and base b > n+2 or 0 if no such prime exists.

%C No prime found for n = 4, 27, 64.

%C Record values: a(3)=10, a(7)=30, a(10)=132, a(12)=143, a(16)=170, a(18)=665, a(28)=1740, a(46)=7426, a(66)=19899, a(100)=21412, a(112)=52601.

%Y Cf. A210339.

%K nonn

%O 2,1

%A _Pierre CAMI_, Nov 13 2017