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Least positive k such that k * Y^n + 1 is prime, where Y = 2^100+277, the first prime greater than a "little googol.".
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%I #4 Dec 15 2017 17:36:50

%S 104,208,696,1522,486,24,96,1020,374,220,198,4228,272,598,854,408,

%T 1826,438,1760,232,170,130,186,1216,4812,4450,1878,1236,434,28,5036,

%U 406,656

%N Least positive k such that k * Y^n + 1 is prime, where Y = 2^100+277, the first prime greater than a "little googol.".

%C Other terms are a(100)=2772, a(150)=3652, a(200)=10242 and a(300)=2740. All values have been proved prime. Primality proof for a(300), which has 9035 digits: PFGW Version 1.2.0 for Windows [FFT v23.8] Primality testing 2740*(1267650600228229401496703205653)^300+1 [N-1, Brillhart-Lehmer-Selfridge] Reading factors from helper file help.txt Running N-1 test using base 2 Calling Brillhart-Lehmer-Selfridge with factored part 99.96% 2740*(1267650600228229401496703205653)^300+1 is prime! (12.1861s+0.0046s)

%Y Cf. A108344.

%K more,nonn

%O 1,1

%A _Jason Earls_, Jul 07 2005