172421875domain: NAppears in sequencesSecond binomial transform of F(n+1).at n=15A081567Expansion of ((1+x)^4-(1+x)x^3)/((1+x)^5-x^5).at n=31A105370Number of paths of length n starting at initial node of the path graph P_9.at n=31A178381a(n) = (3-sqrt(5))*((3+sqrt(5))/10)^(-n)/2 + (3+sqrt(5))*((3-sqrt(5))/10)^(-n)/2.at n=7A179135