86911domain: NAppears in sequencesL.g.f.: Sum_{n>=1} a(n)*x^n/n = Sum_{n>=1} x^n/n * exp( Sum_{k>=1} sigma(n*k)*x^(n*k)/k ).at n=26A203321If n is 0, 1, or prime, a(n) = n; else a(n) = a(n-1) + a(n-2).at n=50A265822Number of n-step self-avoiding walks on the half-Manhattan square lattice.at n=14A336724