login
a(n) is the smallest composite number m such that all n numbers m+4*k^2 for k=1,2,...,n are prime.
2

%I #3 Mar 30 2012 17:37:44

%S 9,15,25,25,247,583,5377,143473,143473,143473,2821813,62087033647,

%T 91450844347

%N a(n) is the smallest composite number m such that all n numbers m+4*k^2 for k=1,2,...,n are prime.

%C There is no further term up to 5*10^8.

%Y Cf. A145741, A145742.

%K more,nonn

%O 1,1

%A _Farideh Firoozbakht_, Oct 17 2008

%E a(12)-a(13) from _Donovan Johnson_, Nov 17 2008