A003304 Number of figure 8's with 2n edges on the square lattice. (Formerly M1850)

2, 8, 32, 144, 708, 3696, 20296, 115624, 676828, 4044744, 24565432

Offset

2,1

References

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

S. G. Whittington and J. P. Valleau, Figure eights on the square lattice: enumeration and Monte Carlo estimation, J. Phys. A 3 (1970), 21-27.

Links

Table of n, a(n) for n=2..12.

Sean A. Irvine, Illustration of initial terms.

Crossrefs

Sequence in context: A150863 A084137 A129400 * A150864 A202814 A054116

Adjacent sequences: A003301 A003302 A003303 * A003305 A003306 A003307

Keyword

nonn,more

Author

N. J. A. Sloane

Extensions

a(9)-a(12) from Sean A. Irvine, Mar 20 2017

Status

approved