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A109490 Value of Product[k/sd(k,3),k=1..n], where sd[k,b] is the sum of the digits of k represented in base b.

%I A109490 #8 Jan 22 2018 03:05:56
%S A109490 1,1,3,6,10,30,70,140,1260,6300,23100,138600,600600,2102100,10510500,
%T A109490 42042000,142942800,1286485200,8147739600,40738698000,285170886000,
%U A109490 1568439873000,7214823415800,43288940494800,216444702474000
%N A109490 Value of Product[k/sd(k,3),k=1..n], where sd[k,b] is the sum of the digits of k represented in base b.
%C A109490 See A109489 for the corresponding base-2 sequence.
%C A109490 For n=601 the sum is not an integer (its denominator is 7).  B-file contains all terms before that.
%H A109490 Robert Israel, <a href="/A109490/b109490.txt">Table of n, a(n) for n = 1..600</a>
%p A109490 P:= 1: A[1]:= P:
%p A109490 for n from 2 to 100 do
%p A109490   P:= P*n/convert(convert(n,base,3),`+`);
%p A109490   A[n]:= P;
%p A109490 od:
%p A109490 seq(A[i],i=1..100); # _Robert Israel_, Jan 21 2018
%Y A109490 Cf. A109489.
%K A109490 nonn,base,easy,fini
%O A109490 1,3
%A A109490 _John W. Layman_, Jun 29 2005