

A019266


Cycle class sequence c(2n) (the number of true cycles of length 2n in which a certain node is included) for square lattice.


0



1, 0, 4, 12, 56, 280, 1488, 8232, 47008, 274824, 1636520, 9890584
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,3


REFERENCES

G. Thimm and W. E. Klee, Zeolite cycle sequences, Zeolites, 19, pp. 422424, 1997.


LINKS

Table of n, a(n) for n=0..11.
G. Thimm, Cycle sequences of crystal structures


MATHEMATICA

(Length@FindCycle[{NearestNeighborGraph[Tuples[Range[2 # + 4], 2], {All, 1.}], {#+2, #+2}}, {2 #}, All]) & /@ Range[11] (* Gabriel B. Apolinario, Jan 07 2017 *)


CROSSREFS

Sequence in context: A149423 A124004 A243785 * A009114 A144012 A197924
Adjacent sequences: A019263 A019264 A019265 * A019267 A019268 A019269


KEYWORD

nonn,more,changed


AUTHOR

Georg Thimm (mgeorg(AT)ntu.edu.sg)


EXTENSIONS

a(11) from Gabriel B. Apolinario, Jan 07 2017


STATUS

approved



