a(n) = floor(p/2) * floor(floor(p/2)/2) * floor(floor(floor(p/2)/2)/2) * ... * 1, where p=prime(n).

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =10a(5) =18a(6) =64a(7) =72a(8) =110a(9) =294a(10) =315a(11) =1296a(12) =2000a(13) =2100a(14) =2530a(15) =6084a(16) =8526a(17) =9450a(18) =33792a(19) =38080a(20) =46656a(21) =53352a(22) =82000a(23) =106480a(24) =248832a(25) =270000a(26) =275400a(27) =322452a(28) =341172a(29) =460992