TST-Romania, 2002
Source: sequence of integers
October 9, 2009
algebrapolynomialinductionDiophantine equationnumber theory proposednumber theory
Problem Statement
The sequence is defined by: a_0\equal{}a_1\equal{}1 and a_{n\plus{}1}\equal{}14a_n\minus{}a_{n\minus{}1} for all .
Prove that 2a_n\minus{}1 is a perfect square for any .