A039783 phi(n) is equal to the product of the dual prime-power components of n-1 (i.e., A008477(n-1)).

5, 17, 51, 73, 109, 433, 17408, 21601, 121501, 1350001, 3294173, 9376762501

Offset

1,1

Comments

a(13) > 3*10^10. - Donovan Johnson

Links

Table of n, a(n) for n=1..12.

Example

phi(17408) = 8192, 17407 = 13^2*103^1, (2^13)*(1^103) = 8192.

Crossrefs

Cf. A000010, A008477.

Sequence in context: A196310 A196283 A196333 * A374185 A103685 A116521

Adjacent sequences: A039780 A039781 A039782 * A039784 A039785 A039786

Keyword

nonn

Author

Olivier Gérard

Extensions

More terms from Naohiro Nomoto, Jun 24 2001

a(12) from Donovan Johnson, Nov 14 2010

Status

approved