42520225774domain: NAppears in sequencesExpansion of (1+2*x+4*x^2+4*x^3+6*x^4+4*x^5+x^6) / (1-3*x-x^2-6*x^3-7*x^4-7*x^5-5*x^6-x^7).at n=18A275908