Rounded total surface area of a regular octahedron with edge length n.

Terms

a(0) =0a(1) =3a(2) =14a(3) =31a(4) =55a(5) =87a(6) =125a(7) =170a(8) =222a(9) =281a(10) =346a(11) =419a(12) =499a(13) =585a(14) =679a(15) =779a(16) =887a(17) =1001a(18) =1122a(19) =1251a(20) =1386a(21) =1528a(22) =1677a(23) =1833a(24) =1995a(25) =2165a(26) =2342a(27) =2525a(28) =2716a(29) =2913