Coefficients of ménage hit polynomials.

Terms

a(0) =0a(1) =2a(2) =3a(3) =4a(4) =40a(5) =210a(6) =1477a(7) =11672a(8) =104256a(9) =1036050a(10) =11338855a(11) =135494844a(12) =1755206648a(13) =24498813794a(14) =366526605705