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A128200 Numbers of divisors of semiprime powers: A000005(A085155(n)). 4
1, 3, 4, 3, 4, 4, 4, 5, 4, 4, 3, 4, 4, 4, 4, 9, 4, 4, 4, 3, 4, 4, 4, 4, 4, 7, 4, 4, 4, 4, 5, 4, 4, 4, 4, 4, 4, 4, 4, 9, 4, 4, 4, 4, 4, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 4, 4, 4, 4, 4, 4, 9, 4, 4, 4, 4, 4, 4, 4, 4, 4, 16, 4, 4, 4, 4, 9, 4, 4, 4, 4, 4, 4, 4, 9, 4, 4, 4, 4, 4, 4, 4, 3, 4, 4, 4, 4, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The range of this sequence is the union of squares and the odd numbers: A128201.

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = (1+A001222(A085155(n))/A001221(A085155(n)))^A001221(A085155(n)).

CROSSREFS

Cf. A005408, A000290.

Sequence in context: A276867 A100867 A220196 * A258168 A061988 A094151

Adjacent sequences:  A128197 A128198 A128199 * A128201 A128202 A128203

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 04 2007

STATUS

approved

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Last modified August 18 14:30 EDT 2018. Contains 313832 sequences. (Running on oeis4.)