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A077812 Squarefree kernel of numbers containing in their decimal representation only the digits 0 and 1. 1
1, 10, 11, 10, 101, 110, 111, 10, 1001, 1010, 1011, 110, 1101, 1110, 1111, 10, 10001, 10010, 10011, 1010, 10101, 10110, 10111, 110, 11001, 11010, 1001, 1110, 11101, 11110, 11111, 10, 100001, 100010, 100011, 10010, 100101, 100110, 100111, 1010 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Not all squarefree kernels of numbers containing in their decimal representation only the digits 0 and 1 also have this property: a(511) = A007947(A007088(511)) = A007947(111111111) = A007947(3*3*37*333667) = 3*37*333667 = 37037037.

LINKS

Table of n, a(n) for n=1..40.

FORMULA

a(n) = A007947(A007088(n)).

EXAMPLE

a(20) = A007947(A007088(20)) = A007947(10100) = A007947(2*2*5*5*101) = 2*5*101 = 1010.

CROSSREFS

Cf. A077813, A077805, A077806.

Sequence in context: A085214 A082492 A004053 * A004288 A065016 A087381

Adjacent sequences:  A077809 A077810 A077811 * A077813 A077814 A077815

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Nov 16 2002

STATUS

approved

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Last modified October 20 22:44 EDT 2019. Contains 328291 sequences. (Running on oeis4.)