Sums of the products of n consecutive quadruples of numbers.

Terms

a(0) =0a(1) =840a(2) =8760a(3) =41520a(4) =134544a(5) =347064a(6) =768264a(7) =1523424a(8) =2780064a(9) =4754088a(10) =7715928a(11) =11996688a(12) =17994288a(13) =26179608a(14) =37102632a(15) =51398592a(16) =69794112a(17) =93113352a(18) =122284152a(19) =158344176a(20) =202447056a(21) =255868536a(22) =320012616a(23) =396417696a(24) =486762720