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A000837
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Number of partitions of n into relatively prime parts. Also aperiodic partitions.
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20
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1, 1, 1, 2, 3, 6, 7, 14, 17, 27, 34, 55, 63, 100, 119, 167, 209, 296, 347, 489, 582, 775, 945, 1254, 1481, 1951, 2334, 2980, 3580, 4564, 5386, 6841, 8118, 10085, 12012, 14862, 17526, 21636, 25524, 31082, 36694, 44582, 52255, 63260, 74170, 88931, 104302
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,4
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COMMENTS
| Starting (1, 1, 2, 3, 6, 7, 14,...), = row sums of triangle A137585. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jan 27 2008
Contribution from Gary W. Adamson (qntmpkt(AT)yahoo.com), Nov 28 2009: (Start)
Triangle A168532 has aerated variants of A000837 in each column starting
with offset 1, row sums = A000041. (End)
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REFERENCES
| H. W. Gould, personal communication.
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LINKS
| T. D. Noe, Table of n, a(n) for n=0..1000
N. J. A. Sloane, Transforms
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FORMULA
| Moebius transform of A000041.
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EXAMPLE
| Of the 11 partitions of 6, we must exclude 6, 4+2, 3+3 and 2+2+2, so a(6)=11-4=7.
For n=6, 2+2+1+1 is periodic because it can be written 2*(2+1), similarly 1+1+1+1+1+1, 3+3 and 2+2+2.
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CROSSREFS
| Cf. A047968, A055892.
Cf. A137585.
A168532 [From Gary W. Adamson (qntmpkt(AT)yahoo.com), Nov 28 2009]
Sequence in context: A191615 A018606 A117087 * A200144 A056498 A018652
Adjacent sequences: A000834 A000835 A000836 * A000838 A000839 A000840
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KEYWORD
| nonn,easy,nice
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| Corrected and extended by David W. Wilson (davidwwilson(AT)comcast.net) Aug 15 1996.
Formula and additional comments from Christian G. Bower (bowerc(AT)usa.net), Jun 11 2000
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