5100819domain: NAppears in sequencesa(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 1, a(2) = 3, a(3) = -3.at n=38A295676Number of partitions of the vertices of the n-ladder graph into total dominating sets.at n=17A392415