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Coordination sequence for AlPO_4-11 structure with respect to node (Y) where decagon, hexagon and square meet and is adjacent to node of type (X).
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%I #18 Mar 30 2012 17:38:44

%S 1,3,5,8,10,13,17,18,20,25,26,28,33,33,36,42,41,43,50,49,51,58,56,59,

%T 67,64,66,75,72,74,83,79,82,92,87,89,100,95,97,108,102,105,117,110,

%U 112,125,118,120,133,125,128,142,133,135,150,141,143,158,148,151

%N Coordination sequence for AlPO_4-11 structure with respect to node (Y) where decagon, hexagon and square meet and is adjacent to node of type (X).

%C There are three types of nodes in this structure.

%C 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.

%H Joseph Myers, <a href="/A072150/b072150.txt">Table of n, a(n) for n = 0..1000</a>

%H M. E. Davis, <a href="http://dx.doi.org/10.1038/nature00785">Ordered porous materials for emerging applications</a>, Nature, 417 (Jun 20 2002), 813-821 (gives structure).

%H N. J. A. Sloane, <a href="/A072150/a072150.gif">AlPO_4-11 structure, after Davis</a>

%H R. J. Mathar, <a href="/A072150/a072150.ps">Illustration of counts and adjacencies</a> (PostScript)

%F Empirical: G.f 1 +x*(3+5*x+8*x^2+7*x^3+8*x^4+9*x^5+8*x^6+7*x^7+8*x^8+5*x^9+3*x^10) / ( (x^6+x^3+1)*(x-1)^2*(1+x+x^2)^2 ) with a(n)= +a(n-3) +a(n-9) -a(n-12). - R. J. Mathar, Sep 30 2011

%Y Cf. A072149-A072154.

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_, Jun 28 2002

%E More terms from _R. J. Mathar_, Mar 29 2007

%E Extended by _Joseph Myers_, Sep 29 2011