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%I #18 Jan 24 2023 10:08:04
%S 1,4,16,37,89,175,336,579,975,1533,2363,3477,5030,7040,9716,13078,
%T 17400,22707,29342,37336,47112,58705,72627,88918,108185,130476,156502,
%U 186315,220741,259839,304554,354953,412111,476101,548137,628299,717946,817168,927478
%N Number of isomorphism classes of nanocones with 4 pentagons and a symmetric boundary of length n
%H Nico Van Cleemput, <a href="/A198015/b198015.txt">Table of n, a(n) for n = 2..75</a>
%H G. Brinkmann and N. Van Cleemput, <a href="https://doi.org/10.1016/j.dam.2011.06.014">Classification and generation of nanocones</a>, Discrete Applied Mathematics, 159 (2011), 1528-1539.
%F Conjectured g.f.: x^2*(-x^11 + x^10 - x^9 + 4*x^8 + 5*x^7 + 10*x^6 + 9*x^5 + 11*x^4 + 4*x^3 + 7*x^2 + 2*x + 1) / ((x - 1)^6*(x + 1)^3*(x^2 + 1)*(x^2 + x + 1)). [_D. S. McNeil_, Oct 20 2011]
%K nonn
%O 2,2
%A _Nico Van Cleemput_, Oct 20 2011