1,1
a(1) = 561 because smallest prime divisor 3 is second prime.
Cf. A002997, A135717, A006931, A135719.
Sequence in context: A048123 A131672 A083732 * A097130 A110889 A205947
Adjacent sequences: A135717 A135718 A135719 * A135721 A135722 A135723
nonn
Artur Jasinski (grafix(AT)csl.pl), Nov 25 2007