The discussion revolves around determining the last digit of the expression 2009 raised to the power of 2009. The subject area involves number theory and modular arithmetic.
Some participants have identified patterns in the last digits and have acknowledged the utility of modular arithmetic in the context of the problem. There appears to be ongoing exploration of these ideas without a definitive conclusion yet.
Participants are considering the implications of factoring 2009 and the relevance of its last digit in the calculations. There is an emphasis on recognizing patterns in the powers of numbers.
micromass said:To simplify dick's post: it suffices to look at 9^1, 9^2, 9^3,..., do you see why?