a(n) = [x^n] Product_{k=1..n} (k + x - k*x^2), for n >= 0.
A322228
a(n) = [x^n] Product_{k=1..n} (k + x - k*x^2), for n >= 0.
Terms
- a(0) =1a(1) =1a(2) =-3a(3) =-21a(4) =75a(5) =1475a(6) =-5005a(7) =-221389a(8) =593523a(9) =57764619a(10) =-89101881a(11) =-23273632371a(12) =953636541
External references
- oeis: A322228