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.

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

Author

John W. Layman, Jun 29 2005

Keywords

• nonn
• base
• easy
• fini

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

Crossrefs

Cf. A109489.

Programs

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