479480601600domain: NAppears in sequencesNumber of stretching pairs in all permutations in S_n.at n=13A216119Expansion of e.g.f. exp(x^4/(1 - x)).at n=14A293050E.g.f.: Product_{m>0} (1 + x^(2*m-1) + x^(4*m-2)/2!).at n=14A293488Expansion of e.g.f. exp(-x^3)/(1-x).at n=15A370701