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A095983 Number of 2-edge-connected labeled graphs on n nodes. 17
0, 0, 0, 1, 10, 253, 11968, 1047613, 169181040, 51017714393, 29180467201536, 32121680070545657, 68867078000231169536, 290155435185687263172693, 2417761175748567327193407488, 40013922635723692336670167608181, 1318910073755307133701940625759574016 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

From Falk Hüffner, Jun 28 2018: (Start)

Equivalently, number of connected bridgeless labeled graphs (graphs that are k-edge connected for k >= 2).

Labeled version of A007146. (End)

LINKS

Table of n, a(n) for n=0..16.

PROG

(PARI) \\ here p is initially A053549, q is A198046 as e.g.f's.

seq(n)={my(v=vector(n));

my(p=x*deriv(log(sum(k=0, n, 2^binomial(k, 2) * x^k / k!) + O(x*x^n))));

my(q=x*exp(p)); p-=q;

for(k=3, n, my(c=polcoeff(p, k)); v[k]=c*(k-1)!; p-=c*q^k);

concat([0], v)} \\ Andrew Howroyd, Jun 18 2018

CROSSREFS

Cf. A013922, A053549, A198046.

Sequence in context: A001536 A114450 A178689 * A059166 A100743 A251588

Adjacent sequences:  A095980 A095981 A095982 * A095984 A095985 A095986

KEYWORD

nonn

AUTHOR

Yifei Chen (yifei(AT)mit.edu), Jul 17 2004

EXTENSIONS

Name corrected and extended by Pavel Irzhavski, Nov 01 2014

Offset corrected by Falk Hüffner, Jun 17 2018

a(12)-a(16) from Andrew Howroyd, Jun 18 2018

STATUS

approved

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Last modified December 11 04:29 EST 2018. Contains 318049 sequences. (Running on oeis4.)