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A135201 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=16. +0
17
210, 2100, 2310, 14490, 21000, 23100 (list; graph; listen)
OFFSET

1,1

EXAMPLE

210^1=210 is multiple of Sum_digits(210)=3

210^2=44100 is multiple of Sum_digits(44100)=9

...

210^16=14305686902419853283210000000000000000 is a multiple of Sum_digits(210^16)=90

while

210^17=3004194249508169189474100000000000000000 is not multiple of Sum_digits(210^17)=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(45000, 16);

CROSSREFS

Cf. A135186, A135187, A135188, A135189, A135190, A135191, A135192, A135193, A135194, A135195, A135196, A135197, A135198, A135199, A135200, A135202.

Sequence in context: A118281 A047633 A104902 this_sequence A064260 A027806 A024407

Adjacent sequences: A135198 A135199 A135200 this_sequence A135202 A135203 A135204

KEYWORD

easy,nonn,base

AUTHOR

Paolo P. Lava & Giorgio Balzarotti (ppl(AT)spl.at), Nov 26 2007

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Last modified July 25 07:41 EDT 2008. Contains 142293 sequences.


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