413376domain: NAppears in sequencesa(n) = a(n-1) + a(n-2) + F(n) - 1, a(0) = a(1) = 0, where F() = Fibonacci numbers A000045.at n=23A006478a(n) = Sum_{k=0..floor(n/2)} T(n-k,k), T given by A026769.at n=23A026779Number of edges in the hyperoctahedral (or cocktail party) graph of order n.at n=24A368757