A077811 Euler's totient of numbers containing in their decimal representation only the digits 0 and 1.

1, 4, 10, 40, 100, 40, 72, 400, 720, 400, 672, 400, 732, 288, 1000, 4000, 9792, 2880, 6440, 4000, 5184, 2688, 10110, 4000, 6912, 2928, 7920, 2880, 10432, 4000, 10800, 40000, 90900, 39168, 59904, 28800, 65520, 25760, 86040, 40000, 66560, 20736

Offset

1,2

Links

Table of n, a(n) for n=1..42.

Formula

a(n) = A000010(A007088(n)).

Example

a(20) = A000010(A007088(20)) = A000010(10100) = A000010(2*2*5*5*101) = 10100*(1-1/2)*(1-1/5)*(1-1/101) = 4000.

Crossrefs

Sequence in context: A186337 A100307 A238721 * A136855 A136860 A136859

Adjacent sequences: A077808 A077809 A077810 * A077812 A077813 A077814

Keyword

nonn,base

Author

Reinhard Zumkeller, Nov 16 2002

Status

approved