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%I M3230 #34 Apr 14 2023 10:52:58
%S 1,1,4,4,9,8,55,21,104,62,429,196,800,698,4674,2070,7721,7154
%N Number of isonemal fabrics of period exactly n.
%D B. Grünbaum and G. C. Shephard, The geometry of fabrics, pp. 77-97 of F. C. Holroyd and R. J. Wilson, editors, Geometrical Combinatorics. Pitman, Boston, 1984. [gives different a(10) which is probably erroneous]
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Branko Grünbaum and G. C. Shephard, <a href="https://doi.org/10.1111/j.1749-6632.1985.tb14560.x">A catalogue of isonemal fabrics</a>, Discrete Geometry and Convexity, 440 (1985), 279-298.
%H B. Grünbaum and G. C. Shephard, <a href="https://doi.org/10.1016/0012-365X(86)90010-5">An extension to the catalogue of isonemal fabrics</a>, Discrete Mathematics, 60, (1986), 155-192.
%F a(n) = A000046(n) + A193140(n) + A262589(n).
%Y Cf. A000046, A193140, A262589.
%K nonn,more
%O 2,3
%A _Simon Plouffe_
%E a(14)-a(19) from second Grünbaum and Shephard paper added by _Sean A. Irvine_, Jun 26 2016
%E a(10) corrected by _Andrey Zabolotskiy_, Apr 14 2023
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