Number of trailing zeros in n!; highest power of 5 dividing n!.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =1a(6) =1a(7) =1a(8) =1a(9) =1a(10) =2a(11) =2a(12) =2a(13) =2a(14) =2a(15) =3a(16) =3a(17) =3a(18) =3a(19) =3a(20) =4a(21) =4a(22) =4a(23) =4a(24) =4a(25) =6a(26) =6a(27) =6a(28) =6a(29) =6