Susceptibility series H_4 for 2-dimensional Ising model (divided by 2) for 1 particle excitation.

Terms

a(0) =1a(1) =16a(2) =90a(3) =328a(4) =886a(5) =2016a(6) =3986a(7) =7208a(8) =12050a(9) =19096a(10) =28802a(11) =41936a(12) =59030a(13) =81048a(14) =108586a(15) =142816a(16) =184386a(17) =234688a(18) =294410a(19) =365176a(20) =447702a(21) =543856a(22) =654370a(23) =781368a(24) =925586a(25) =1089416a(26) =1273586a(27) =1480768a(28) =1711670a(29) =1969256