a(n) = denominator(r(n)) where r(n) = (n/2)*(Pi/2)^cos(Pi*(n-1))*((n/2-1/2)!/(n/2)!)^2.

A380950

a(n) = denominator(r(n)) where r(n) = (n/2)*(Pi/2)^cos(Pi*(n-1))*((n/2-1/2)!/(n/2)!)^2.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =3a(4) =16a(5) =45a(6) =128a(7) =175a(8) =2048a(9) =11025a(10) =32768a(11) =43659a(12) =262144a(13) =693693a(14) =2097152a(15) =2760615a(16) =67108864a(17) =703956825a(18) =2147483648a(19) =2807136475a(20) =17179869184a(21) =44801898141a(22) =137438953472a(23) =178837328943

External references