3,2

Table of n, a(n) for n=3..38.

3*2*3*4*5*6*7/(2*3*5*7) -1 = 71 prime twin of 73

3*2*3*4*5*6*7/(2*3*5*7) +1 = 73 prime twin of 71, so k(4)=3 as p(4)=7

Sequence in context: A032100 A226593 A023371 * A091109 A219391 A123982

Adjacent sequences: A124083 A124084 A124085 * A124087 A124088 A124089

nonn

Pierre CAMI, Nov 25 2006

approved