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A066184 Sum of the first moments of all partitions of n. 1
1, 5, 13, 32, 61, 123, 208, 367, 590, 957, 1459, 2266, 3328, 4938, 7097, 10205, 14299, 20100, 27626, 38023, 51485, 69600, 92882, 123863, 163235, 214798, 280141, 364530, 470660, 606557, 776233, 991370, 1258827, 1594741, 2010142, 2528445 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

The first element of each partition is given weight 1.

FORMULA

a(n) = 1/2*(A066183(n) + A066186(n)). - Vladeta Jovovic (vladeta(AT)eunet.rs), Mar 23 2003

EXAMPLE

a(3)=13 because the first moments of all partitions of 3 are {3}.{1},{2,1}.{1,2} and {1,1,1}.{1,2,3}, resulting in 3,4,6; summing to 13.

MATHEMATICA

(* First do <<DiscreteMath`Combinatorica` *) Table[ Plus@@ Map[ #.Range[ Length[ # ] ]&, Partitions[ n ] ], {n, 40} ]

CROSSREFS

Cf. A066185.

Sequence in context: A062403 A066688 A046789 * A146924 A001981 A141025

Adjacent sequences:  A066181 A066182 A066183 * A066185 A066186 A066187

KEYWORD

easy,nonn

AUTHOR

Wouter Meeussen (wouter.meeussen(AT)pandora.be), Dec 15 2001

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Last modified February 15 09:46 EST 2012. Contains 205761 sequences.