1,1

a(n) = 2*A039716(n) = 2*A000142[A000040(n)]. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 31 2007

Sequence in context: A052598 A032071 A076030 this_sequence A009506 A085116 A104129

Adjacent sequences: A131488 A131489 A131490 this_sequence A131492 A131493 A131494

easy,nonn

Giovanni Teofilatto (g.teofilatto(AT)tiscalinet.it), Jul 29 2007