A054591 Denominators of rational numbers that belong to the Cantor set.

1, 3, 4, 9, 10, 12, 13, 27, 28, 30, 36, 39, 40, 81, 82, 84, 90, 91, 108, 117, 120, 121, 146, 182, 205, 243, 244, 246, 252, 270, 273, 324, 328, 351, 360, 363, 364, 386, 438, 546, 615, 656, 671, 729, 730, 732, 738, 756, 757, 810, 819, 820, 949, 972, 984

Offset

1,2

Links

David Radcliffe, Table of n, a(n) for n = 1..321

D. Jordan and R. Schayer, Rational points on the Cantor middle thirds set, Penn State, REU 2003.

J. Nagy, Rational Points in Cantor Sets, Fibonacci Quarterly 39.3, (2001), 238-241.

C. Wall, Terminating Decimals in the Cantor Ternary Set, Fibonacci Quarterly 28.2 (1990), 98-101.

Example

10 belongs to the sequence because 1/10 = 0.00220022... (base 3) is in the Cantor set. - David Radcliffe, May 02 2015

Crossrefs

Reminiscent of (but different from) A005836.

Sequence in context: A010400 A010439 A005836 * A121153 A276986 A283984

Adjacent sequences: A054588 A054589 A054590 * A054592 A054593 A054594

Keyword

nonn,frac

Author

Michael J. Hardy, Apr 14 2000

Status

approved