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High temperature series in v = tanh(J/kT) for residual correlation function (correction to susceptibility) for the spin-1/2 Ising model on square lattice.
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Previous name was: Susceptibility for square lattice.
Susceptibility High temperature series in v = tanh(J/kT) for residual correlation function (correction to susceptibility) for spin-1/2 Ising model on square lattice.
G.f.: ((1-3*v)^2*xi(v) - (1-v)^2 + 2*v*u(v)) / (8*v^7*(1+v)^2), where xi(v) is the g.f. of A002906 and u(v) is the g.f. of A002908 (odd powers only!) ; the actual "residual correlation function" is the numerator of this expression [Sykes & Fisher]. - Andrey Zabolotskiy, Feb 28 2021
Terms New name and terms a(10) and beyond from Andrey Zabolotskiy, Feb 28 2021
2, 2, 20, 38, 146, 368, 1070, 2824, 7680, 19996, 53024, 136350, 355254, 906254, 2331416, 5909810, 15067236, 37992680, 96210436, 241564514, 608469654, 1522388638, 3818281784, 9525139886, 23806217352, 59237754234, 147621207142, 366533832540, 911151508282
M. F. Sykes and M. E. Fisher, Antiferromagnetic susceptibility of the plane square and honeycomb Ising lattices, Physica, 28 (1962), 919-938.
M. F. Sykes and M. E. Fisher, <a href="https://doi.org/10.1016/0031-8914(62)90080-0">Antiferromagnetic susceptibility of the plane square and honeycomb Ising lattices</a>, Physica, 28 (1962), 919-938.
G.f.: ((1-3*v)^2*xi(v) - (1-v)^2 + 2*v*u(v)) / (8*v^7*(1+v)^2), where xi(v) is the g.f. of A002906 and u(v) is the g.f. of A002908 (odd powers only!) [Sykes & Fisher]. - Andrey Zabolotskiy, Feb 28 2021
Terms a(10) and beyond from Andrey Zabolotskiy, Feb 28 2021
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editing
_N. J. A. Sloane (njas(AT)research.att.com)_.