48171200domain: NAppears in sequencesOne half of triple factorial numbers.at n=7A034000a(n) = (n+1)*a(n-3), a(0)=a(1)=a(2)=1 for n>1.at n=22A081406An invertible triangle of ratios of triple factorials.at n=37A112333Triple factorials n!!!: a(n) = n*a(n-3).at n=23A161474