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%I #11 Sep 28 2018 23:20:21
%S 2,10,52,276,1470,7838,41798,222902,1188696,6339088,33805118,
%T 180276062,961376842,5126833922,27340398612,145800977348,777527983398,
%U 4146404063814,22111958704510,117918733974142,628837454333128,3353466668484240,17883379272566534,95368550166928198
%N a(n) is the number of row convex polyglasses (polyiamonds which need only touch at corners) with n cells.
%H Adam Gruber, <a href="https://devweb3000.cis.strath.ac.uk/~xpb16190/LatticeAnimals/LatticeAnimals.jar">Java program to count lattice animals</a>.
%F G.f.: (2*z*(1+z)*(1-z)^3)/(1-7z+9z^2+z^3-9z^4+3z^5).
%e The only diglasses that are not row convex are "two mountains" and its 180-degree rotation. So a(2) = A319324(2) - 2 = 10.
%t Rest@CoefficientList[Series[(2z(1+z)(1-z)^3)/(1-7z+9z^2+z^3-9z^4+3z^5),{z,0,20}],z]
%Y Cf. A319324 (fixed polyglasses), A319326 (column convex polyglasses), A238823 (row convex polyiamonds).
%K nonn
%O 1,1
%A _David Bevan_, Sep 27 2018
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