A218253 The number of steps it takes, by taking the smallest number so that it minus the number of ones in its binary representation is the previous number, to reach a number which has no others that satisfy this property.

1, 0, 2, 1, 0, 0, 3, 2, 0, 1, 1, 0, 0, 0, 3, 2, 0, 1, 2, 0, 0, 1, 2, 0, 1, 1, 0, 0, 0, 0, 3, 2, 0, 1, 2, 0, 0, 1, 3, 0, 1, 2, 0, 0, 0, 1, 3, 0, 1, 2, 0, 0, 2, 1, 0, 1, 1, 0, 0, 0, 0, 0, 3, 2, 0, 1, 2, 0, 0, 1

Offset

1,3

Comments

A218252 is divided into groups with length the numbers with odd position in this sequence.

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Example

For n=7, the numbers you get are 7,8,10,12, and because this takes 3 steps, the 7th term is 3.

Prog

(PARI) f(n)=for(k=n+1, n+log(n)\log(2)+1, if(k-hammingweight(k)==n, return(k)))
a(n)=my(k); while(n=f(n), k++); k \\ Charles R Greathouse IV, Oct 29 2012

Crossrefs

Cf. A218252, A218254.

Sequence in context: A281449 A280605 A362427 * A037872 A037854 A362633

Adjacent sequences: A218250 A218251 A218252 * A218254 A218255 A218256

Keyword

nonn,easy

Author

Nico Brown, Oct 24 2012

Status

approved