1,1

a(1) = 6 is 1-semiprime equal 2*3;

a(2) = 1155 is 2-semiprime equal (3*5)*(7*11);

a(3) = 86822723 is 3-semiprime equal (11*13)*(17*19)*(23*29).

Sequence in context: A004806 A125536 A003763 this_sequence A159717 A160857 A160005

Adjacent sequences: A113156 A113157 A113158 this_sequence A113160 A113161 A113162

nonn

Giovanni Teofilatto (g.teofilatto(AT)tiscalinet.it), Jan 05 2006