The Gauss factorial n_10!.

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =3a(5) =3a(6) =3a(7) =21a(8) =21a(9) =189a(10) =189a(11) =2079a(12) =2079a(13) =27027a(14) =27027a(15) =27027a(16) =27027a(17) =459459a(18) =459459a(19) =8729721a(20) =8729721a(21) =183324141a(22) =183324141a(23) =4216455243a(24) =4216455243a(25) =4216455243a(26) =4216455243a(27) =113844291561a(28) =113844291561