Expansion of e.g.f. (2 - exp(x))^4.

Terms

a(0) =1a(1) =-4a(2) =8a(3) =8a(4) =-40a(5) =-184a(6) =-232a(7) =1928a(8) =19160a(9) =116936a(10) =600728a(11) =2826248a(12) =12623960a(13) =54550856a(14) =230564888a(15) =959736968a(16) =3952166360a(17) =16149893576a(18) =65626404248a(19) =265592398088