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A129431 Number of isomorphism classes of 5-regular multigraphs of order 2n, loops allowed. 8
3, 32, 727, 42703, 5988679, 1639714425, 757559332934, 541249158493444, 564262722366313620, 822164422526588575949 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

First seven terms were computed using software at http://users.cecs.anu.edu.au/~bdm/nauty/

LINKS

Table of n, a(n) for n=1..10.

R. C. Read, The enumeration of locally restricted graphs (I), J. London Math. Soc. 34 (1959) 417-436. [From Jason Kimberley, Oct 05 2009]

FORMULA

a(n)=N\{S_{2n}[S_5] * S_{5n}[S_2]\} [From Jason Kimberley, Oct 05 2009]

CROSSREFS

Cf. A129430, A129420, A129427, A129429, A129433, A129435, A129437

Sequence in context: A264334 A278069 A295385 * A297558 A283716 A202806

Adjacent sequences:  A129428 A129429 A129430 * A129432 A129433 A129434

KEYWORD

nonn

AUTHOR

Brendan McKay, Apr 15 2007

EXTENSIONS

Using equation (5.8) of Read 1959, new terms a(8),a(9),a(10) were computed in MAGMA during 2009 by Jason Kimberley, Dec 22 2010

STATUS

approved

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Last modified January 16 23:44 EST 2019. Contains 319206 sequences. (Running on oeis4.)