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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.
2
1, 1, 3, 6, 10, 30, 70, 140, 1260, 6300, 23100, 138600, 600600, 2102100, 10510500, 42042000, 142942800, 1286485200, 8147739600, 40738698000, 285170886000, 1568439873000, 7214823415800, 43288940494800, 216444702474000
OFFSET
1,3
COMMENTS
See A109489 for the corresponding base-2 sequence.
For n=601 the sum is not an integer (its denominator is 7). B-file contains all terms before that.
LINKS
MAPLE
P:= 1: A[1]:= P:
for n from 2 to 100 do
P:= P*n/convert(convert(n, base, 3), `+`);
A[n]:= P;
od:
seq(A[i], i=1..100); # Robert Israel, Jan 21 2018
CROSSREFS
Cf. A109489.
Sequence in context: A068195 A080506 A109163 * A130760 A154134 A001465
KEYWORD
nonn,base,easy,fini
AUTHOR
John W. Layman, Jun 29 2005
STATUS
approved