a(n) is the denominator of Sum_{k=0..n} (-1)^k / (k!)^2.

A354305

a(n) is the denominator of Sum_{k=0..n} (-1)^k / (k!)^2.

Terms

    a(0) =1a(1) =1a(2) =4a(3) =9a(4) =192a(5) =1800a(6) =103680a(7) =529200a(8) =232243200a(9) =8230118400

External references