A307313 a(n) is the denominator of n/2^(length of the binary representation of n).

2, 2, 4, 2, 8, 4, 8, 2, 16, 8, 16, 4, 16, 8, 16, 2, 32, 16, 32, 8, 32, 16, 32, 4, 32, 16, 32, 8, 32, 16, 32, 2, 64, 32, 64, 16, 64, 32, 64, 8, 64, 32, 64, 16, 64, 32, 64, 4, 64, 32, 64, 16, 64, 32, 64, 8, 64, 32, 64, 16, 64, 32, 64, 2, 128, 64, 128, 32, 128, 64

Offset

1,1

Links

Table of n, a(n) for n=1..70.

Formula

a(n) = denominator(n/2^A070939(n)).

a(n) = denominator(n/A062383(n)).

a(n) = 2^A070940(n).

Example

For n=1, 1 = 1_2,  a(1) = denominator(1/(2^1)) = denominator(1/2) = 2;
For n=2, 2 = 10_2, a(2) = denominator(2/(2^2)) = denominator(1/2) = 2;
For n=3, 3 = 11_2, a(3) = denominator(3/(2^2)) = denominator(3/4) = 4.

Prog

(PARI) a(n) = denominator(n/(2^(#binary(n))));

Crossrefs

Cf. A062383, A070939, A000265 (numerators), A078267 (analog in base 10).

Sequence in context: A364557 A297112 A259192 * A338042 A131999 A113416

Adjacent sequences: A307310 A307311 A307312 * A307314 A307315 A307316

Keyword

nonn,base,frac

Author

Michel Marcus, Apr 02 2019

Status

approved