1997015domain: NAppears in sequencesExpansion of 1/((1-x)*(1-2*x)*(1-x-2*x^3)).at n=18A003230Expansion of series related to Liouville's Last Theorem: g.f. Sum_{t>=1} (-1)^(t+1) *x^(t*(t+1)/2) / ( (1-x^t)^7 * Product_{i=1..t} (1-x^i) ).at n=24A059824