A151946 - OEIS

A151946

a(1) = 8127; thereafter a(n) = (a(n-1) with digits sorted into descending order) - (a(n-1) with digits sorted into ascending order) (see the Kaprekar map, A151949).

8127, 7443, 3996, 6264, 4176, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174, 6174

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

OFFSET

1,1

COMMENTS

Similar in spirit to the RATS (Reverse, Add Then Sort) sequences.

Converges to the fixed point 6174. For the list of fixed points see A099009.

The initial value 1001 is the smallest number that converges to 6174 - see A151967.

LINKS

Table of n, a(n) for n=1..39.

John Tierney, "TierneyLab" column, New York Times, Section C, Aug 18 2009

Index entries for the Kaprekar map

Index entries for RATS sequences