OFFSET
0,3
FORMULA
a(n) = Sum_{k=0..m} binomial(m,k)*binomial(m+e,k)*Bell(n-k), with m = floor(n/2), e = n mod 2 and where Bell(n) is the Bell exponential number A000110(n).
CROSSREFS
KEYWORD
nonn
AUTHOR
Francesca Aicardi, Nov 13 2022
STATUS
approved