A055921 Array giving susceptibility of 2-dimensional Ising model for 1 particle excitation (read by antidiagonals).

1, 2, 2, 2, 8, 2, 2, 16, 16, 2, 2, 24, 48, 24, 2, 2, 32, 104, 104, 32, 2, 2, 40, 180, 296, 180, 40, 2, 2, 48, 280, 656, 656, 280, 48, 2, 2, 56, 400, 1240, 1772, 1240, 400, 56, 2, 2, 64, 544, 2104, 4032, 4032, 2104, 544, 64, 2, 2, 72, 708, 3304, 7972, 10728, 7972

Offset

0,2

Links

Table of n, a(n) for n=0..61.

A. J. Guttmann, Indicators of solvability for lattice models, Discrete Math., 217 (2000), 167-189 (chi_1 of Section 3).

I. Syozi and S. Naya, Symmetrical properties of two-dimensional Ising lattices, Prog. Theor. Phys., 24 (1960), 829-839.

Formula

G.f.: A(x, y)=(1-x^2)*(1-y^2)/(1-x-y-xy)^2 * (1 - 16*x^2*y^2/((1-x^2)^2*(1-y^2)^2))^(1/4).

Example

Array begins:
1 2 2 2 2...
2 8 16 24 32...
2 16 48 104 180...
2 24 104 296 656...
2 32 180 656 1772...

Crossrefs

Column 4 is A055920/2.

Sequence in context: A160689 A179976 A137508 * A029605 A367189 A054271

Adjacent sequences: A055918 A055919 A055920 * A055922 A055923 A055924

Keyword

nonn,tabl

Author

Christian G. Bower, Jun 19 2000

Status

approved