OFFSET
1,2
COMMENTS
FORMULA
a(n) = a(n/9) if n==0 (mod 9); a(n) = a(n - floor(n/9)) otherwise.
PROG
(PARI) a(n, m=9)=while(n>=m, if(n%m, n-=n\m, n\=m)); n \\ M. F. Hasler, Mar 07 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
M. F. Hasler, Mar 07 2015
STATUS
approved