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Smallest prime of the form 2n*(2n+2)*(2n+4)*...*(2n+2k) + 1 where k is a nonnegative integer.
1

%I #11 Nov 18 2018 10:33:59

%S 3,5,7,13441,11,13,929901772801,17,19,7380172801,23,20530298881,21841,

%T 29,31,59535361,7591472824321,37,63841,41,43,

%U 32611799187695769164215700373287163408678912000001,47

%N Smallest prime of the form 2n*(2n+2)*(2n+4)*...*(2n+2k) + 1 where k is a nonnegative integer.

%e a(4) = 8*10*12*14 + 1 = 13441, 8 + 1, 8*10 + 1, 8*10*12 + 1 are all composite.

%t Do[p = k = 2*n; While[ !PrimeQ[p+1], k += 2; p *= k]; Print[p+1], {n, 1, 30}] (* _Ryan Propper_, Aug 15 2005 *)

%K nonn,more

%O 1,1

%A _Amarnath Murthy_, Jul 20 2005

%E More terms from _Ryan Propper_, Aug 15 2005