Divide n! repeatedly by i! for i from floor(n/2) down through 2; a(n) = remaining quotient.

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =3a(5) =15a(6) =5a(7) =35a(8) =35a(9) =105a(10) =7a(11) =77a(12) =77a(13) =1001a(14) =143a(15) =429a(16) =2145a(17) =36465a(18) =12155a(19) =230945a(20) =46189a(21) =323323a(22) =29393a(23) =676039a(24) =676039a(25) =16900975a(26) =1300075a(27) =2340135a(28) =334305a(29) =9694845