Row 3 of array in A226513.

Terms

a(0) =1a(1) =4a(2) =24a(3) =184a(4) =1704a(5) =18424a(6) =227304a(7) =3147064a(8) =48278184a(9) =812387704a(10) =14872295784a(11) =294192418744