MathDB

1

Part of 1997 Hungary-Israel Binational

Problems(2)

Hungary-Israel Binational 1997_1

Source:

11/4/2008
Is there an integer N N such that \left(\sqrt{1997}\minus{}\sqrt{1996}\right)^{1998}\equal{}\sqrt{N}\minus{}\sqrt{N\minus{}1}?
USAMTSnumber theory unsolvednumber theory
An odd number of letters

Source: Hungary-Israel, 1997

2/1/2007
Determine the number of distinct sequences of letters of length 1997 which use each of the letters AA, BB, CC (and no others) an odd number of times.
functioncombinatorics proposedcombinatorics