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A077811
Euler's totient of numbers containing in their decimal representation only the digits 0 and 1.
0
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
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
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Nov 16 2002
STATUS
approved