%I #8 Jul 19 2023 07:48:42

%S 1,2,13,150,1978,28603,438273,6992052,114915180,1932233883,

%T 33081722359,574755965137,10107627041697,179576579730534,

%U 3218352405778284,58114340679967608,1056284029850962674,19310039426151335622,354818596435147647654,6549556302551204621664,121394125733645986376838

%N G.f. satisfies A(x) = (1 + x) * (1 + x*A(x)^6).

%F a(n) = Sum_{k=0..n} binomial(6*k+1,k) * binomial(6*k+1,n-k) / (6*k+1).

%o (PARI) a(n) = sum(k=0, n, binomial(6*k+1, k)*binomial(6*k+1, n-k)/(6*k+1));

%Y Cf. A073157, A364336, A364337, A364338.

%Y Cf. A239109, A364333, A364340.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Jul 19 2023