489349324800domain: NAppears in sequencesSixth degree product sequence: a(n) = product( 1 +4*cos(k*Pi/n)^2 +16*cos(k*Pi/n)^4 +64*cos(k*Pi/n)^6, k=1..(n-1)/2 ).at n=24A152116A sixth degree product form sequence: a(n)=Product[(1 + 4*Sin[k*Pi/n]^2 + 16*Sin[k*Pi/n]^4 + 64*Sin[k*Pi/n]^6), {k, 1, Floor[(n - 1)/2]}].at n=24A152143