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%I
%S 13,223,1577,7018,23431,64316,153190,327718,644573,1185025,2061259,
%T 3423422,5467399,8443318,12664784,18518842,26476669,37104995,51078253,
%U 69191458,92373815,121703056,158420506,203946878,259898797,328106053
%N Seventh column of A046741.
%D I. P. Goulden and D. M. Jackson, Combinatorial Enumeration, Wiley, N.Y., 1983,(2.3.14).
%F G.f.: (2*x^6+14*x^5+72*x^4+207*x^3+289*x^2+132*x+13)/(1-x)^7. Generally, g.f. for k-th column of A046741 is coefficient of y^k in expansion of (1-y)/((1-y-y^2)*(1-y)-(1+y)*x).
%Y Cf. dumbbells: A002940, A002941, A002889, A046741, A055608, A062123-A062127.
%K easy,nonn
%O 0,1
%A _Vladeta Jovovic_, Jun 04 2001
%E More terms from Larry Reeves (larryr(AT)acm.org), Jun 06 2001
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