A005398 Number of n-step polygons on f.c.c. lattice.

8, 33, 168, 970, 6168, 42069, 301376, 2241420, 17173224, 134806948, 1079802216, 8798329080, 72748583832, 609220407150, 5158999447488

Offset: 3

Author

N. J. A. Sloane

Keywords

• nonn
• more
• nice

References

• A. J. Guttmann, Polygons, Polyominoes and Polycubes, Lecture Notes in Physics Volume 775, 2009, Chapter 16.
• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• M. F. Sykes et al., Lattice constant systems and graph theory, J. Math. Phys., 7 (1966), 1557-1572.
• Index entries for sequences related to f.c.c. lattice

Crossrefs

Equals A001337(n) / (2n).

Programs

Mathematica

A001337 = Cases[Import["https://oeis.org/A001337/b001337.txt", "Table"], {, }][[All, 2]];
a[n_] := A001337[[n]]/(2n);
a /@ Range[3, 17] (* Jean-François Alcover, Jan 20 2020 *)

Extensions

More terms from Ruperto Corso, Dec 19 2011

a(15) and a(16) from Sean A. Irvine, Mar 30 2017

a(17) from Bert Dobbelaere, Jan 14 2019