Ceiling of Gamma(n+3/7)/Gamma(3/7).

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =6a(5) =23a(6) =123a(7) =788a(8) =5853a(9) =49331a(10) =465113a(11) =4850461a(12) =55433830a(13) =688963307a(14) =9251792973a(15) =133490155744