|
|
A073047
|
|
Least k such that x(k)=0 where x(1)=n and x(k)=k*floor(x(k-1)/k).
|
|
4
|
|
|
2, 3, 3, 4, 4, 5, 5, 5, 5, 6, 6, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 16, 16
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Presumably a(n) = sqrt(Pi*n)+O(1).
|
|
EXAMPLE
|
If x(1)=4, x(2)= 2*floor(4/2)=4, x(3)=3*floor(4/3)=3; x(4)=4*floor(3/4)=0 hence a(4)=4.
|
|
MAPLE
|
f:= proc(n, k) option remember;
if n = 0 then return k-1 fi;
procname(k*floor(n/k), k+1)
end proc:
|
|
MATHEMATICA
|
a[n_] := Module[{x}, x[1] = n; x[k_] := x[k] = k Floor[x[k-1]/k]; For[k = 1, True, k++, If[x[k] == 0, Return[k]]]];
|
|
PROG
|
(PARI) a(n)=if(n<0, 0, s=n; c=1; while(s-s%c>0, s=s-s%c; c++); c)
|
|
CROSSREFS
|
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|