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

A146313

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

Terms

    a(0) =3a(1) =243a(2) =23763a(3) =2328483a(4) =228167523a(5) =22358088723

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