A007282 Number of hexaflexagons with 3n triangles that can be folded from a straight strip of paper. (Formerly M3489)

1, 1, 1, 4, 14, 74, 434, 2876, 19848, 143306, 1062149, 8058223, 62259820, 488630360, 3886211100, 31267852668

Offset

1,4

References

M. Kosters, A theory of hexaflexagons, Nieuw Archief Wisk., 17 (1999), 349-362.

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..16.

Crossrefs

Cf. A001683, A000207.

Sequence in context: A159483 A088127 A242739 * A222900 A222485 A009347

Adjacent sequences: A007279 A007280 A007281 * A007283 A007284 A007285

Keyword

nonn,more,nice

Author

N. J. A. Sloane, frb6006(AT)cs.rit.edu (Frank R. Bernhart)

Extensions

More terms from Mike Godfrey (m.godfrey(AT)umist.ac.uk), Apr 02 2002

Status

approved