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%I #24 Mar 30 2012 17:38:44
%S 1,3,6,8,10,13,16,19,20,22,28,31,30,33,38,40,42,43,46,53,54,52,58,63,
%T 62,65,68,70,76,77,76,83,86,84,90,93,92,99,102,100,106,109,108,115,
%U 116,114,124,127,122,129,134,132,138,139,138,149,150,144,154,159
%N Coordination sequence for AlPO_4-11 structure with respect to node (X) where decagon and two hexagons meet.
%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="/A072149/b072149.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="/A072149/a072149.ps">Illustration of counts and adjacencies</a> (PostScript)
%F Empirical: G.f. 1 +x*(3 +6*x +11*x^2 +13*x^3 +15*x^4 +15*x^5 +16*x^6 +15*x^7 +15*x^8 +13*x^9 +11*x^10 +6*x^11 +3*x^12) / ( (1+x^2)*(x^6+x^3+1)*(x-1)^2*(1+x+x^2)^2 ) with a(n)= -a(n-2) +a(n-3) +a(n-5) +a(n-9) +a(n-11) -a(n-12) -a(n-14). - R. J. Mathar, Sep 30 2011
%Y Cf. A072150-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
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