33556500domain: NAppears in sequencesNumber of even sequences with period 2n.at n=16A000208Number of cycles induced by iterating the Gray-coding of an n-bit number: a(n+1) = a(n) + 2^n/C_n, where C_n = least power of 2 >= n (C_n is the length of the cycle), with a(0) = 1.at n=30A007886