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A050318
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Number of ways to write n as an mterm, where an mterm is an unordered sum which is either 2, or 1 + an unordered product of mterms.
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3
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1, 1, 1, 2, 2, 3, 3, 5, 6, 8, 8, 12, 12, 15, 17, 23, 23, 31, 31, 41, 44, 52, 52, 69, 72, 84, 90, 108, 108, 135, 135, 161, 169, 192, 198, 246, 246, 277, 289, 342, 342, 404, 404, 464, 491, 543, 543, 644, 650, 734, 757, 853, 853, 978, 994, 1123, 1154, 1262, 1262
(list; graph; refs; listen; history; internal format)
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OFFSET
| 2,4
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FORMULA
| Shifts left under transform T where Ta has Dirichlet g.f.: prod{n=1 to inf}(1/(1-1/n^s)^a(n)).
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EXAMPLE
| The different ways of writing the numbers 2 through 7 as mterms are:
2=2
3=1+2
4=1+(1+2)
5=1+(1+1+2)=1+2*2
6=1+(1+1+1+2)=1+(1+2*2)
7=1+(1+1+1+1+2)=1+(1+1+2*2)=1+2*(1+2)
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CROSSREFS
| Cf. A001055, A050319, A050365, A050366.
Sequence in context: A097450 A062303 A180682 * A130841 A002095 A029017
Adjacent sequences: A050315 A050316 A050317 * A050319 A050320 A050321
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KEYWORD
| nonn,eigen,nice,easy
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AUTHOR
| Christian G. Bower (bowerc(AT)usa.net), Sep 15 1999.
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