946583628domain: NAppears in sequencesExpansion of (1-x)*(1+x)/(1-x-2*x^2+x^4).at n=33A052535a(n) is its own 4th difference.at n=16A055990A trisection of 1/(1-x-x^4).at n=22A099234a(n) = Sum_{k=0..2*n} binomial(3*k,2*n-k).at n=11A392431