246546091domain: NAppears in sequencesa(n) = 1 + Product_{d|n, d < n} a(d).at n=23A343390a(n) = 1 + Product_{d|n, d < n} a(d).at n=39A343390a(n) = 1 + Product_{d|n, d < n} a(d).at n=53A343390