a(n) = floor(n!/R(n)!), where R(n) = digit reversal of n (A004086).

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =1a(9) =3628800a(10) =1a(11) =0a(12) =0a(13) =0a(14) =0a(15) =0a(16) =0a(17) =0a(18) =0a(20) =106661318400a(21) =1a(22) =0a(23) =0a(24) =0a(25) =0a(26) =0a(27) =0a(28) =0a(32) =1a(33) =0