login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A006778 Number of n-step spirals on hexagonal lattice.
(Formerly M2652)
0
1, 3, 7, 15, 31, 59, 110, 198, 347, 592, 997, 1641, 2666, 4266, 6741, 10525, 16268, 24882, 37717, 56683, 84504, 125031, 183716, 268125, 388873, 560647, 803723, 1146013, 1625731 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice.

REFERENCES

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

G. Szekeres and A. J. Guttmann, Spiral self-avoiding walks on the triangular lattice, J. Phys. A 20 (1987), 481-493.

LINKS

Table of n, a(n) for n=1..29.

G. Nebe and N. J. A. Sloane, Home page for hexagonal (or triangular) lattice A2

CROSSREFS

Sequence in context: A229006 A023424 A276647 * A007574 A034480 A218281

Adjacent sequences:  A006775 A006776 A006777 * A006779 A006780 A006781

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane.

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 16 21:59 EST 2019. Contains 320200 sequences. (Running on oeis4.)