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A047968
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a(n) = Sum_{d|n} p(d), where p(d) = A000041 = number of partitions of d.
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12
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1, 3, 4, 8, 8, 17, 16, 30, 34, 52, 57, 99, 102, 153, 187, 261, 298, 432, 491, 684, 811, 1061, 1256, 1696, 1966, 2540, 3044, 3876, 4566, 5846, 6843, 8610, 10203, 12610, 14906, 18491, 21638, 26508, 31290, 38044, 44584, 54133, 63262, 76241
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Row sums of triangle A137587. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Jan 27 2008
Row sums of triangle A168021. [From Omar E. Pol (info(AT)polprimos.com), Nov 20 2009]
Row sums of triangle A168017. Row sums of triangle A168018. [From Omar E. Pol (info(AT)polprimos.com), Nov 25 2009]
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..1000
N. J. A. Sloane, Transforms
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FORMULA
| G.f.: Sum_{k>0} (-1+1/Product_{i>0} (1-z^(k*i))). - Vladeta Jovovic (vladeta(AT)eunet.rs), Jun 22 2003
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MAPLE
| with(combinat): with(numtheory): a := proc(n) c := 0: l := sort(convert(divisors(n), list)): for i from 1 to nops(l) do c := c+numbpart(l[i]) od: RETURN(c): end: for j from 1 to 60 do printf(`%d, `, a(j)) od: - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 14 2007
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CROSSREFS
| Cf. A000041, A047966.
Inverse Moebius transform of A000041. Cf. A000837, A047966, A055893.
Cf. A137587.
Cf. A168021. [From Omar E. Pol (info(AT)polprimos.com), Nov 20 2009]
Cf. A168017, A168018. [From Omar E. Pol (info(AT)polprimos.com), Nov 25 2009]
Sequence in context: A097689 A002246 A030014 * A181778 A125219 A075562
Adjacent sequences: A047965 A047966 A047967 * A047969 A047970 A047971
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KEYWORD
| nonn
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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