A005397 Number of n-step polygons on Kagome lattice. (Formerly M3186)

4, 0, 0, 4, 28, 80, 120, 120, 264, 1080, 3120, 6440, 11960, 26688, 70448, 179340, 415796, 935560, 2195536, 5374468, 13145420, 31504224, 74955600, 180228984, 438624648, 1069909344, 2600077824, 6310088640, 15363918432

Offset

3,1

References

M. E. Fisher and M. F. Sykes, Excluded-volume problem and the Ising model of ferromagnetism, Phys. Rev. 114 (1959), 45-58.

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=3..31.

Crossrefs

Cf. A001665.

Sequence in context: A189885 A372821 A151673 * A259124 A273515 A308225

Adjacent sequences: A005394 A005395 A005396 * A005398 A005399 A005400

Keyword

nonn

Author

N. J. A. Sloane.

Extensions

a(14)-a(22) from Sean A. Irvine, Jun 12 2016

a(23)-a(31) from Sean A. Irvine, Aug 15 2020

Status

approved