a(n) = 4*(4*n+3)!/(3*n+4)!.A370058a(n) = 4*(4*n+3)!/(3*n+4)!.Terms a(0) =1a(1) =4a(2) =44a(3) =840a(4) =23256a(5) =850080a(6) =38750400a(7) =2120489280a(8) =135566323200External referencesoeis: A370058