a(n) = numerator( [(x*y*z*u)^n] 1/sqrt(1 - (x + y + z + u*(x*y + x*z + y*z))) ).

A381197

a(n) = numerator( [(x*y*z*u)^n] 1/sqrt(1 - (x + y + z + u*(x*y + x*z + y*z))) ).

Terms

    a(0) =1a(1) =9a(2) =1575a(3) =107415a(4) =143918775a(5) =13539797271

External references