

A127258


Triangular array read by rows: B(n,k) (n>=1, 0<=k<=n(n1)/2) is such that SUM B(n,k)*q^(n*(n1)/2k) gives the expectation of the number of connected components in a random graph on n labeled vertices where every edge is present with probability q.


2



1, 1, 2, 1, 0, 3, 3, 2, 6, 3, 4, 0, 6, 4, 6, 40, 105, 130, 60, 18, 15, 10, 0, 10, 5, 24, 270, 1350, 3925, 7260, 8712, 6485, 2445, 60, 330, 18, 45, 20, 0, 15, 6, 120, 2016, 15750, 75810, 250950, 603435, 1084104, 1471305, 1502550, 1128820, 589281, 182721
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OFFSET

1,3


COMMENTS

Rowreversed version of A125210, see A125210 for further details.


LINKS

Table of n, a(n) for n=1..53.


EXAMPLE

The array starts with
1
1, 2
1, 0, 3, 3
2, 6, 3, 4, 0, 6, 4
6, 40, 105, 130, 60, 18, 15, 10, 0, 10, 5
...


CROSSREFS

Cf. A125210 (rowreversed version), A125209 (dual version).
Sequence in context: A215063 A113020 A228821 * A154557 A049242 A108887
Adjacent sequences: A127255 A127256 A127257 * A127259 A127260 A127261


KEYWORD

sign,tabf


AUTHOR

Max Alekseyev, Jan 09 2007


STATUS

approved



