Partial sums of A243980.

Terms

a(0) =4a(1) =20a(2) =52a(3) =112a(4) =196a(5) =328a(6) =492a(7) =716a(8) =992a(9) =1340a(10) =1736a(11) =2244a(12) =2808a(13) =3468a(14) =4224a(15) =5104a(16) =6056a(17) =7164a(18) =8352a(19) =9708a(20) =11192a(21) =12820a(22) =14544a(23) =16508a(24) =18596a(25) =20852a(26) =23268a(27) =25908a(28) =28668a(29) =31716