A047710 Low temperature series associated with square lattice.

0, -4, 8, 36, -144, 236, -328, 580, -1088, 1836, -3096, 5668, -10736, 20668, -40328

Offset

1,2

Links

Table of n, a(n) for n=1..15.

M. F. Sykes and M. E. Fisher, Antiferromagnetic susceptibility of the plane square and honeycomb Ising lattices, Physica, 28 (1962), 919-938.

Formula

G.f.: (2*(1-y^2)*u(y^2) + 4*((2-y)^2*xi(y^2)-1)) / (1+y)^2, where u(x) is the g.f. of A002909 and xi(x) is the g.f. of A002979. - Andrey Zabolotskiy, Mar 03 2021

Crossrefs

Cf. A002909, A002979, A002907.

Sequence in context: A100214 A229535 A309618 * A335991 A063580 A003049

Adjacent sequences: A047707 A047708 A047709 * A047711 A047712 A047713

Keyword

sign,more

Author

N. J. A. Sloane

Status

approved