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A072151 Coordination sequence for AlPO_4-11 structure with respect to node (Z) where decagon, hexagon and square meet and is not adjacent to node of type (X). 1
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 (list; graph; refs; listen; history; text; internal format)
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), 813-821 (gives structure).

LINKS

Joseph Myers, Table of n, a(n) for n = 0..1000

N. J. A. Sloane, AlPO_4-11 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) *(x-1)^2 *(1+x+x^2)^2 ) - R. J. Mathar, Sep 30 2011

CROSSREFS

Cf. A072149-A072154.

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

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Last modified August 23 04:06 EDT 2017. Contains 290958 sequences.