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A077813 Squarefree numbers containing in their decimal representation only the digits 0 and 1. 2
1, 10, 11, 101, 110, 111, 1001, 1010, 1011, 1101, 1110, 1111, 10001, 10010, 10011, 10101, 10110, 10111, 11001, 11010, 11101, 11110, 11111, 100001, 100010, 100011, 100101, 100110, 100111, 101001, 101010, 101011, 101101, 101110, 101111, 110001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

EXAMPLE

a(51) = 1000110 = 2*3*5*17*37*53.

MATHEMATICA

Union[Select[FromDigits/@Tuples[{1, 0}, 6], SquareFreeQ]] (* Harvey P. Dale, Nov 07 2013 *)

PROG

(Haskell)

a077813 n = a077813_list !! (n-1)

a077813_list = filter ((== 1) . a008966) $ tail $

   map ((foldr (\d v -> v * 10 + d) 0) . map fromIntegral) a030308_tabf

-- Reinhard Zumkeller, Nov 08 2013

CROSSREFS

Cf. A077812, A020449, A005117.

Cf. A008966, A030308.

Sequence in context: A348109 A125099 A055611 * A203075 A104326 A205598

Adjacent sequences:  A077810 A077811 A077812 * A077814 A077815 A077816

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Nov 16 2002

STATUS

approved

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Last modified September 27 07:17 EDT 2022. Contains 357052 sequences. (Running on oeis4.)