a(n)=n^6-n^5-n^4-n^3-n^2-n.

Terms

a(0) =0a(1) =-4a(2) =2a(3) =366a(4) =2732a(5) =11720a(6) =37326a(7) =98042a(8) =224696a(9) =465012a(10) =888890a(11) =1594406a(12) =2714532a(13) =4424576a(14) =6950342a(15) =10577010a(16) =15658736a(17) =22628972a(18) =32011506a(19) =44432222a(20) =60631580a(21) =81477816a(22) =107980862a(23) =141306986a(24) =182794152a(25) =233968100a(26) =296559146a(27) =372519702