a(n) = ceiling((2n+1/n)^n).A197716a(n) = ceiling((2n+1/n)^n).Terms a(0) =3a(1) =21a(2) =255a(3) =4633a(4) =110409a(5) =3243618a(6) =113177497a(7) =4570858600a(8) =209655304353External referencesoeis: A197716