164833

Appears in sequences

• Real part of (1 + 2*i)^n, where i is sqrt(-1).at n=16A006495
• Smallest leg in right triangle with relatively prime sides and hypotenuse 5^n.at n=7A036842
• a(n) = 5^n*cos(2*n*arctan(1/2)) or denominator of tan(2*n*arctan(1/2)).at n=8A066771
• Let (A,B)=(a(2*n),a(2*n+1)), then (A,B) is (even,odd), gcd(A,B)=1 and A^2 + B^2 = 5^n. Note: a(0)=0.at n=33A098122
• a(1) = 1, a(2) = 2; thereafter a(2n+1) = |a(2n)^2-a(2n-1)^2|, a(2n+2) = 2*a(2n-1)*a(2n).at n=8A100686
• Real part of (1 + 2i)^(2^n) where i is sqrt(-1).at n=4A120905
• Numerator of real part of (3*i - 1)^(-n).at n=16A124869
• Real part of (2 + i)^n, where i = sqrt(-1).at n=16A139011
• Real part of (4 + 3i)^n.at n=8A139030
• Values of x such that x^2 + y^2 = 5^n with x and y coprime and 0 < x < y.at n=15A230710
• Expansion of g.f. (1 - theta_4(x))/2 / Product_{n>=1} (1 - x^(2*n))^3.at n=36A370150