|
Search: id:A135202
|
|
|
| A135202 |
|
Numbers n that raised to the powers from 1 to k (with k>=1) are multiple of the sum of their digits (n raised to k+1 must not be a multiple). Case k=17. |
|
+0 17
|
| |
|
|
OFFSET
|
1,1
|
|
|
EXAMPLE
|
3900^1=3900 is multiple of Sum_digits(3780)=12
3900^2=15210000 is multiple of Sum_digits(3600)=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
|
Cf. A135186, A135187, A135188, A135189, A135190, A135191, A135192, A135193, A135194, A135195, A135196, A135197, A135198, A135199, A135200, A135201.
Sequence in context: A108005 A065696 A014891 this_sequence A115468 A066386 A068240
Adjacent sequences: A135199 A135200 A135201 this_sequence A135203 A135204 A135205
|
|
KEYWORD
|
easy,nonn,base,bref
|
|
AUTHOR
|
Paolo P. Lava & Giorgio Balzarotti (ppl(AT)spl.at), Nov 26 2007
|
|
|
Search completed in 0.002 seconds
|