165800domain: NAppears in sequencesThe path length of the Fibonacci tree of order n.at n=19A178523a(n) = 2*a(n-1) + 2*a(n-2) - 3*a(n-3), where a(0) = 2, a(1) = 4, a(2) = 8.at n=14A288309Number of permutations p of [n] such that | |p(i) - p(i-1)| - |p(i+1) - p(i)| | <= 1.at n=17A338765