A058057 Triangle giving coefficients of ménage hit polynomials.

1, 1, 0, 1, 1, 0, 1, 3, 1, 1, 1, 6, 6, 8, 3, 1, 10, 20, 38, 35, 16, 1, 15, 50, 134, 213, 211, 96, 1, 21, 105, 385, 915, 1479, 1459, 675, 1, 28, 196, 952, 3130, 7324, 11692, 11584, 5413, 1, 36, 336, 2100, 9090, 28764, 65784, 104364, 103605, 48800

Offset: 0

Author

N. J. A. Sloane, Dec 02 2000

Keywords

• nonn
• easy
• nice
• tabl

Comments

Triangle of coefficients of polynomials P(n; x) = Permanent(M), where M=[m(i,j)] is n X n matrix defined by m(i,j)=x if 0<=i-j<=1 else m(i,j)=1. - Vladeta Jovovic, Jan 23 2003

Examples

			1; 1,0; 1,1,0; 1,3,1,1; 1,6,6,8,3; ...
		

References

• J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 198.

Links

• T. D. Noe, Rows n = 0..100 of triangle, flattened

Crossrefs

Diagonals give A000271, A000426, A000222, A000386, A000450, A058085, A058086.

Cf. A080018, A080061.

Programs

Maple

V := proc(n) local k; add( binomial(2*n-k,k)*(n-k)!*(x-1)^k, k=0..n); end; W := proc(r,s) coeff( V(r),x,s ); end; a := (n,k)->W(n,n-k);

Mathematica

max = 9; f[x_, y_] := Sum[n!*((x*y)^n/(1 + x*(y-1))^(2*n+1)), {n, 0, max}]; Flatten[ MapIndexed[ Take[#1, #2[[1]]] & , CoefficientList[ Series[f[x, y], {x, 0, max}, {y, 0, max}], {x, y}]]] (*Jean-François Alcover, Jun 29 2012, after Vladeta Jovovic *)

Formula

G.f.: Sum(n!*(x*y)^n/(1+x*(y-1))^(2*n+1),n=0..infinity). [Vladeta Jovovic, Dec 13 2009]