

A072151


Coordination sequence for AlPO_411 structure with respect to node (Z) where decagon, hexagon and square meet and is not adjacent to node of type (X).


2



1, 3, 5, 7, 11, 14, 15, 18, 22, 24, 26, 28, 31, 36, 37, 37, 43, 47, 46, 49, 53, 55, 59, 60, 61, 68, 70, 68, 74, 78, 77, 82, 85, 85, 91, 93, 92, 99, 101, 99, 107, 110, 107, 114, 118, 116, 122, 124, 123, 132, 133, 129, 139, 143, 138, 145, 149, 147, 155, 156
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OFFSET

0,2


COMMENTS

There are three 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), 813821 (gives structure).


LINKS

Joseph Myers, Table of n, a(n) for n = 0..1000
N. J. A. Sloane, AlPO_411 structure, after Davis
R. J. Mathar, Illustration of counts and adjacencies (PostScript)


FORMULA

Empirical: g.f. 1 +x *(3 +5*x +10*x^2 +13*x^3 +16*x^4 +16*x^5 +16*x^6 +16*x^7 +16*x^8 +13*x^9 +10*x^10 +5*x^11 +3*x^12) ) / ( (1+x^2) *(x^6+x^3+1) *(x1)^2 *(1+x+x^2)^2 )  R. J. Mathar, Sep 30 2011


CROSSREFS

Cf. A072149A072154.
Sequence in context: A123677 A133954 A087325 * A280018 A029626 A111622
Adjacent sequences: A072148 A072149 A072150 * A072152 A072153 A072154


KEYWORD

nonn,easy


AUTHOR

N. J. A. Sloane, Jun 28 2002


EXTENSIONS

More terms from R. J. Mathar, Mar 29 2007
Extended by Joseph Myers, Sep 29 2011


STATUS

approved



