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A007832 Number of point labeled 5,6-free two-graphs with n nodes. 0
1, 1, 2, 8, 52, 457, 4979, 64591, 972906, 16701834, 322063458, 6894918021, 162316253829, 4168330738093, 115980086558470, 3476156853885992, 111665862911781864, 3827642575341002133, 139457935266705019299, 5382149182666970080019, 219344947692643001216702 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..21.

P. J. Cameron, Counting two-graphs related to trees, Elec. J. Combin., Vol. 2, #R4.

FORMULA

STIRLING transform of A007831. - Sean A. Irvine, Feb 03 2018

CROSSREFS

Cf. A007831.

Sequence in context: A027329 A136794 A125787 * A111088 A006351 A300697

Adjacent sequences:  A007829 A007830 A007831 * A007833 A007834 A007835

KEYWORD

nonn

AUTHOR

Peter J. Cameron

STATUS

approved

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Last modified November 16 22:20 EST 2019. Contains 329208 sequences. (Running on oeis4.)