Exact asymptotic expansion for the resistance between center node and a   node on the cobweb network boundary
  We analyze the resistance between two notes in a cobweb network of resistors. Based on an exact expression, we derive the asymptotic expansions for the resistance between the center node and a node on the boundary of the M by N cobweb network of resistors with resistors r and s in the two spatial directions. All coefficients in this expansion are expressed through analytical functions. 
Nickolay Izmailian and Ralph Kenna
cond-mat.stat-mech