OFFSET
1,1
FORMULA
Positive integers n such that A195860(n)=18.
EXAMPLE
3900^1=3900 is multiple of Sum_digits(3900)=12
3900^2=15210000 is multiple of Sum_digits(3900^2)=9
...
3900^17 is a multiple of Sum_digits(3900^17)=108
while
3900^18 is not multiple of Sum_digits(3900^18)=99
MAPLE
readlib(log10); P:=proc(n, m) local a, i, k, w, x, ok; for i from 1 by 1 to n do a:=simplify(log10(i)); if not (trunc(a)=a) then ok:=1; x:=1; while ok=1 do w:=0; k:=i^x; while k>0 do w:=w+k-(trunc(k/10)*10); k:=trunc(k/10); od; if trunc(i^x/w)=i^x/w then x:=x+1; else if x-1=m then print(i); fi; ok:=0; fi; od; fi; od; end: P(50000, 17);
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Paolo P. Lava and Giorgio Balzarotti, Nov 26 2007
EXTENSIONS
Terms a(4) onward from Max Alekseyev, Sep 24 2011
STATUS
approved