Meromorphic functions sharing one value by weight

The uniqueness of meromorphic fuctions sharing one value was studied. Using the concept of weighted sharing, we proved the following theorem. For two meromorphic functions f and g which are not polynominals of degree less than a positive integer k, if f nf (k) and g ng (k) share (1,2), where n is another positive integer not less than k+10, then f nf (k) identically equals g ng (k) or f nf (k)g ng (k) identically equals 1. Particularly for k =1, we improved the results of Yang [Yang CC, Hua XH, Uniqueness and value-sharing of meromorphic functions, Annales Academi? Scientiarum Fennic? Mathematica, 1997, 22: 395-406], and Fang [Fang ML, Hua XH, Entire function that share one value, Journal of Nanjing University, 1996, 13(1): 44-48. (In Chinese)].