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%I #24 Feb 22 2018 12:35:55
%S 1,4,8,16,27,35,48,66,83,113,146,174,203,231,267,311,365,418,466,509,
%T 556,617,691,768,833,897,954,1021,1110,1197,1280,1372,1457,1535,1639,
%U 1755,1856,1950,2064,2165,2275,2405,2513,2635,2745,2871,3010
%N Coordination sequence for "bar" 3D tiling with respect to first type of node.
%C First 127 terms computed by _Davide M. Proserpio_ using ToposPro.
%H Davide M. Proserpio, <a href="/A299894/b299894.txt">Table of n, a(n) for n = 0..127</a>
%H V. A. Blatov, A. P. Shevchenko, D. M. Proserpio, <a href="http://pubs.acs.org/doi/pdf/10.1021/cg500498k">Applied Topological Analysis of Crystal Structures with the Program Package ToposPro</a>, Cryst. Growth Des. 2014, 14, 3576-3586.
%H Reticular Chemistry Structure Resource (RCSR), <a href="http://rcsr.net/nets/bar">The bar tiling (or net)</a>
%F Conjectured recurrence, found by gfun, using the command rec:=gfun[listtorec](t1, a(n)); (where t1 is a list of the initial terms) suggested by _Paul Zimmermann_. (Note: this should not be used to extend the sequence.)
%F a(n+1)=2*a(n+2)-2*a(n+3)+a(n+4)-a(n+7)+3*a(n+8)-4*a(n+9)+4*a(n+10)-2*a(n+11)+2*a(n+14) -4*a(n+15)+4*a(n+16)-3*a(n+17)+a(n+18)-a(n+21)+2*a(n+22)-2*a(n+23)+a(n+24),
%F with a(0) = 1, a(1) = 4, a(2) = 9, a(3) = 17, a(4) = 28, a(5) = 41, a(6) = 56, a(7) = 73, a(8) = 93, a(9) = 117, a(10) = 146, a(11) = 180, a(12) = 216, a(13) = 253, a(14) = 291, a(15) = 329, a(16) = 369, a(17) = 414, a(18) = 466, a(19) = 524, a(20) = 586, a(21) = 650, a(22) = 712, a(23) = 773.
%Y Cf. A299896 (second type), A299895 (partial sums).
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Feb 21 2018