A085873 - OEIS

A085873

a(1) = 2; a(n)= smallest prime of the form k*a(n-1) + 1 where k itself is a multiple of n.

%I #7 Dec 05 2013 19:56:18

%S 2,5,31,373,22381,134287,3760037,481284737,25989375799,6237450191761,

%T 411671712656227,64220787174371413,73468580527480896473,

%U 1028560127384732550623,185140822929251859112141

%N a(1) = 2; a(n)= smallest prime of the form k*a(n-1) + 1 where k itself is a multiple of n.

%e a(2)= 5 = 2*2 + 1, a(3) = 6*5 + 1, a(4) = 12*31 + 1; 2,6 and 12 are respectively multiples of 2, 3 and 4.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Jul 07 2003

%E More terms from _Ray Chandler_, Jul 08 2003

%E Corrected by _T. D. Noe_, Nov 15 2006