A003610 Symmetries in unrooted (1,3) trees on 2n vertices. (Formerly M1565)

2, 6, 8, 8, 56, 24, 168, 240, 608, 920, 5680, 6104, 18416, 43008, 148152, 325608, 980840, 2421096, 7336488, 19769312, 58192608, 164776248, 502085760, 1427051544, 4261678656, 12615722288, 37914214232, 113567513528, 343641240328, 1039134670952

Offset

1,1

References

Kathleen A. McKeon, The expected number of symmetries in locally-restricted trees I, pp. 849-860 of Y. Alavi et al., eds., Graph Theory, Combinatorics and Applications. Wiley, NY, 2 vols., 1991.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

Table of n, a(n) for n=1..30.

Kathleen A. McKeon, Letter to N. J. A. Sloane, July 25 1991

Kathleen A. McKeon, The expected number of symmetries in locally-restricted trees I, pp. 849-860 of Y. Alavi et al., eds., Graph Theory, Combinatorics and Applications. Wiley, NY, 2 vols., 1991. [Annotated scanned copy]

Index entries for sequences related to trees

Crossrefs

Sequence in context: A328910 A064165 A320573 * A201776 A206476 A077477

Adjacent sequences: A003607 A003608 A003609 * A003611 A003612 A003613

Keyword

nonn

Author

N. J. A. Sloane, Mira Bernstein

Extensions

More terms from Sean A. Irvine, Feb 24 2019

Status

approved