a(n) = cos(2*n*arcsin(sqrt(3))) = (-1)^n*cosh(2*n*arcsinh(sqrt(2))).

A146311

a(n) = cos(2*n*arcsin(sqrt(3))) = (-1)^n*cosh(2*n*arcsinh(sqrt(2))).

Terms

    a(0) =1a(1) =-5a(2) =49a(3) =-485a(4) =4801a(5) =-47525a(6) =470449a(7) =-4656965a(8) =46099201a(9) =-456335045a(10) =4517251249a(11) =-44716177445a(12) =442644523201

External references