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A029934
Denominator of n * Product_{d|n} (1 + 1/d).
2
1, 1, 1, 1, 1, 1, 1, 4, 3, 5, 1, 6, 1, 7, 5, 32, 1, 27, 1, 20, 21, 11, 1, 64, 5, 13, 27, 49, 1, 375, 1, 512, 11, 17, 35, 5832, 1, 19, 39, 3200, 1, 147, 1, 242, 135, 23, 1, 24576, 7, 625, 17, 676, 1, 6561, 55, 10976, 57, 29
OFFSET
1,8
LINKS
MAPLE
with(numtheory): f := proc(n) local i, j; j := n; for i in divisors(n) do j := j*(1+1/i); od; end;
MATHEMATICA
dp[n_]:=Denominator[n*Times@@(1+1/#&/@Divisors[n])]; Array[dp, 60] (* Harvey P. Dale, Mar 23 2012 *)
CROSSREFS
Cf. A029933 (numerators).
Sequence in context: A152191 A292612 A316254 * A246665 A274260 A011397
KEYWORD
nonn
AUTHOR
STATUS
approved