Imaginary part of (n + i)^4.

Terms

a(0) =0a(1) =0a(2) =24a(3) =96a(4) =240a(5) =480a(6) =840a(7) =1344a(8) =2016a(9) =2880a(10) =3960a(11) =5280a(12) =6864a(13) =8736a(14) =10920a(15) =13440a(16) =16320a(17) =19584a(18) =23256a(19) =27360a(20) =31920a(21) =36960a(22) =42504a(23) =48576a(24) =55200a(25) =62400a(26) =70200a(27) =78624a(28) =87696a(29) =97440