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%I M3503 #15 Nov 08 2017 02:24:47
%S 1,1,4,15,62,262,1148,5123,23316,107570,502664,2372786,11302858,
%T 54256236,262226900,1274944859,6231845040,30605344282,150948390672,
%U 747356368322,3713140528364,18506907541124,92509837573736,463660345091686
%N Number of blobs with vertical symmetry.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H R. C. Read, <a href="http://dx.doi.org/10.1007/BF02188172">On the enumeration of a class of plane multigraphs</a>, Aequat. Math. 31 (1986) no 1, 47-63.
%F a(n) = coefficient of x^(2n+1) in x + D(x)^3/(1-D(x)^2) where D(x) = Sum_{k=0..infinity} A007162(k) * x^(2*k+1). - _Sean A. Irvine_, Nov 06 2017
%Y Cf. A007162.
%K nonn
%O 0,3
%A _N. J. A. Sloane_.
%E a(9) corrected and more terms from _Sean A. Irvine_, Nov 06 2017
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