Nearest integer to Gamma(n + 6/7)/Gamma(6/7).

Terms

a(0) =1a(1) =1a(2) =2a(3) =5a(4) =18a(5) =85a(6) =499a(7) =3422a(8) =26889a(9) =238158a(10) =2347553a(11) =25487720a(12) =302211543a(13) =3885576978a(14) =53842995268a(15) =799953072548