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A062868 Number of permutations of degree n with barycenter 0. 14
1, 2, 4, 14, 46, 282, 1394, 12658, 83122, 985730, 8012962, 116597538, 1127575970, 19410377378, 217492266658, 4320408974978, 55023200887938, 1238467679662722 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The barycenter or signcenter of a permutation is the sum of the signs of the difference between initial and final positions of the objects.

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

(4,1,3,5,2) has difference (3,-1,0,1,-3) and signs (1,-1,0,1,-1) with total 0.

CROSSREFS

Cf. A062866, A062867, A179567, A196687, A196688.

Sequence in context: A263741 A263742 A263743 * A054936 A006443 A152103

Adjacent sequences:  A062865 A062866 A062867 * A062869 A062870 A062871

KEYWORD

nice,nonn

AUTHOR

Olivier Gérard, Jun 26 2001

EXTENSIONS

One more term from Vladeta Jovovic, Jun 28 2001

a(11)-a(14) from Hugo Pfoertner, Sep 23 2004

a(15)-a(18) from R. H. Hardin, Jul 18 2010

STATUS

approved

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Last modified November 19 16:10 EST 2017. Contains 294936 sequences.