Sum of even integers <= n times the sum of odd integers <= n.

Terms

a(0) =0a(1) =0a(2) =2a(3) =8a(4) =24a(5) =54a(6) =108a(7) =192a(8) =320a(9) =500a(10) =750a(11) =1080a(12) =1512a(13) =2058a(14) =2744a(15) =3584a(16) =4608a(17) =5832a(18) =7290a(19) =9000a(20) =11000a(21) =13310a(22) =15972a(23) =19008a(24) =22464a(25) =26364a(26) =30758a(27) =35672a(28) =41160a(29) =47250