OFFSET
1,1
FORMULA
Positive integers n such that A195860(n)=15.
EXAMPLE
60^1=60 is multiple of Sum_digits(60)=6
60^2=3600 is multiple of Sum_digits(3600)=9
...
60^14=7836416409600000000000000 is a multiple of Sum_digits(7836416409600000000000000)=54
while
60^15=470184984576000000000000000 is not multiple of Sum_digits(470184984576000000000000000)=63
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(30000, 14);
MATHEMATICA
msdQ[n_]:=Module[{b=Boole[Divisible[#, Total[IntegerDigits[#]]]&/@(n^Range[ 15])]}, Total[b]==14&&Last[b]==0]; Select[Range[22*10^5], msdQ] (* Harvey P. Dale, Apr 07 2019 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Paolo P. Lava and Giorgio Balzarotti, Nov 26 2007
EXTENSIONS
Terms a(10) onward from Max Alekseyev, Sep 24 2011
Definition clarified by Harvey P. Dale, Apr 07 2019
STATUS
approved