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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 (list; graph; refs; listen; history; text; internal format)
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

Robert Israel, Table of n, a(n) for n = 1..600

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

Adjacent sequences:  A109487 A109488 A109489 * A109491 A109492 A109493

KEYWORD

nonn,base,easy,fini

AUTHOR

John W. Layman, Jun 29 2005

STATUS

approved

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Last modified November 22 00:32 EST 2019. Contains 329383 sequences. (Running on oeis4.)