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%I #40 Jan 24 2017 20:41:15
%S 3,2,1,1,8,1,2,1,10,2,2,1,2,1,2,167,2,1,12,1,2,2,29028,1,2,3,10,2,
%T 26850,1,8,1,42,2,6,2,24,1,2,3,2,1,2,1,2,2,140,1,2,2,22,2,8,1,2064,2,
%U 468,6,2,1,362,1,2,2,6,3,26,1,2,3,20,1,2,1,28,2,38,5,3024,1,2,81,858,1
%N Least number k such that k*n^k - 1 is prime. a(n) = 0 if no such number exists.
%C a(n) = 1 iff n-1 is prime.
%C a(145) is either 0 or > 275000. - _Robert G. Wilson v_, Jan 23 2017
%H Robert G. Wilson v, <a href="/A240235/b240235.txt">Table of n, a(n) for n = 1..144</a>
%H Steven Harvey, <a href="http://harvey563.tripod.com/">Generalized Woodall Primes</a>
%e 1*1^1 - 1 = 0 is not prime. 2*1^2 - 1 = 1 is not prime. 3*1^3 - 1 = 2 is prime. Thus, a(1) = 3.
%o (PARI) a(n)=k=1;while(!ispseudoprime(k*n^k-1),k++);return(k); n=1;while(n<100,print(a(n));n+=1)
%Y Cf. A066049, A239787, A281141.
%K nonn
%O 1,1
%A _Derek Orr_, Apr 02 2014
%E a(23) and a(29) given using link. - _Derek Orr_, Aug 16 2014
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