OFFSET
0,2
COMMENTS
There are two types of nodes in this structure.
The coordination sequence with respect to a particular node gives the number of nodes that can be reached from that node in n steps along edges.
REFERENCES
M. E. Davis, Ordered porous materials for emerging applications, Nature, 417 (Jun 20 2002), 813-821 (gives structure).
LINKS
Joseph Myers, Table of n, a(n) for n = 0..1000
N. J. A. Sloane, VPl-5 structure, after Davis
FORMULA
Empirical G.f.: (x^2+x+1)^2*(x^6+x^3+1)/((x-1)^2*(x^2+1)*(x^6+x^5+x^4+x^3+x^2+x+1)). [Colin Barker, Nov 18 2012]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jun 28 2002
EXTENSIONS
Extended by Joseph Myers, Sep 30 2011
STATUS
approved