Main diagonal of A292131.

Terms

a(0) =1a(1) =-1a(2) =-2a(3) =6a(4) =12a(5) =45a(6) =-150a(7) =-203a(8) =-840a(9) =-1872a(10) =6390a(11) =8580a(12) =30084a(13) =69108a(14) =165802a(15) =-494565a(16) =-514320a(17) =-1997296a(18) =-4202298a(19) =-10175526a(20) =-18908420a(21) =49930440a(22) =54032770a(23) =190735688a(24) =405256872a(25) =948210600a(26) =1751280726a(27) =3624555168a(28) =-7676955468a(29) =-6724059944