-9653287

Appears in sequences

• Real part of (1 + 2*i)^n, where i is sqrt(-1).at n=20A006495
• a(n) = 5^n*cos(2*n*arctan(1/2)) or denominator of tan(2*n*arctan(1/2)).at n=10A066771
• Real part of (2 + i)^n, where i = sqrt(-1).at n=20A139011