OFFSET
1,3
FORMULA
a(n) = the coefficient of (x1*...*xn)^(n*(n-1)/2) in 1/Product(1 - x1^(n-1)*x2^(n-2)*...*xn^0), where the product is taken over all permutations of the variables x1, ..., xn.
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Max Alekseyev, Aug 25 2022
STATUS
approved