a(n) = n^6 - n^2.

Terms

a(0) =0a(1) =0a(2) =60a(3) =720a(4) =4080a(5) =15600a(6) =46620a(7) =117600a(8) =262080a(9) =531360a(10) =999900a(11) =1771440a(12) =2985840a(13) =4826640a(14) =7529340a(15) =11390400a(16) =16776960a(17) =24137280a(18) =34011900a(19) =47045520a(20) =63999600a(21) =85765680a(22) =113379420a(23) =148035360a(24) =191102400a(25) =244140000a(26) =308915100