A218253 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

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