1,1

A159000(1)=3360=phi(33)*sigma(60) so a(1)=33.

A159000(5)=451584=phi(4515)*sigma(84) so a(5)=4515.

Cf. A000010, A000203, A159000.

Sequence in context: A138839 A033353 A104781 this_sequence A105701 A022989 A023475

Adjacent sequences: A158998 A158999 A159000 this_sequence A159002 A159003 A159004

base,more,nonn

Farideh Firoozbakht (mymontain(AT)yahoo.com), Jun 07 2009