s(n) = floor(n^(n/5)/n!!!!!).

Terms

a(0) =1a(1) =0a(2) =0a(3) =0a(4) =1a(5) =1a(6) =1a(7) =1a(8) =1a(9) =2a(10) =2a(11) =2a(12) =2a(13) =3a(14) =4a(15) =6a(16) =5a(17) =5a(18) =7a(19) =10a(20) =16a(21) =12a(22) =14a(23) =18a(24) =26a(25) =39a(26) =31a(27) =35a(28) =45a(29) =64