G.f.:(5*x^18-20*x^17+30*x^16+58*x^15-745*x^14+2790*x^13-5270*x^12+5010*x^11-711*x^10-4380*x^9+6270*x^8-4470*x^7+1535*x^6+178*x^5-450*x^4+210*x^3-40*x^2+1)/(x-1)^10。例如,具有n个节点和k条边的同胚不可约多重图是(1+x*y)^(-1/2)*exp(x*y/2+x^2*y^2/4)*Sum_{k>=0}1/(1-x)^二项式(k,2)*xp(-x^2*y*k^2/(2*(1+x*y))-x^2*y*k/2)*y^k/k!。
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