70607118400domain: NAppears in sequencesa(n) = (1 + 3^n - 2*3^(n/2))/4 if n is even, (1 + 3^n - 4*3^((n-1)/2))/4 if n odd.at n=23A107767a(n) = ((3^(n-1) - 1)^2)/4.at n=12A238976a(0) = 0; for n >= 1, one quarter of the number of points on the elliptic curve y^2 = x^3 - x defined over GF(3^n).at n=24A382171