a(n) = 10*9*8*7*6*5*4*3*2*1 - 20*19*18*17*16*15*14*13*12*11 + 30*19*18*17*16*15*14*13*12*11 - ... + (up to the n-th term).
A319893
a(n) = 10*9*8*7*6*5*4*3*2*1 - 20*19*18*17*16*15*14*13*12*11 + 30*19*18*17*16*15*14*13*12*11 - ... + (up to the n-th term).
Terms
- a(0) =10a(1) =90a(2) =720a(3) =5040a(4) =30240a(5) =151200a(6) =604800a(7) =1814400a(8) =3628800a(9) =3628800a(10) =3628780a(11) =3628420a(12) =3621960a(13) =3512520a(14) =1768320a(15) =-24278400a(16) =-387072000a(17) =-5075481600a(18) =-60945696000a(19) =-670438944000a(20) =-670438943970a(21) =-670438943130a(22) =-670438919640a(23) =-670438286280a(24) =-670421843280
External references
- oeis: A319893