|49 |50 |35 |119 |120 |169 |- !4 |17 |12 |288 |289 |204 |696 |697 |985 |- !5 |41 |29 |1681 |1682 |1189 |4059 |4060 |5741 |- !6 |99 |70 |9800 |9801 |6930 |23660 |23661 |33461 |} Pythagorean triples The equality occurs exactly when which becomes with the substitutions and . Hence the n-th solution is and . The table above shows that, in one order or the other, an and are and while . Notes References External links —The numerators of the same sequence of approximations Integer sequences Recurrence relations Unsolved problems in mathematics