Level: Lib Thy Top: 2
Hypotheses:- n : {1 + 1...}
f:
((n - 1) + 1) 
(n - 1).
i:
((n - 1) + 1).
j:{(i + 1)..((n - 1) + 1)
}. f i = f j- f :
(n + 1) 
n
Conclusion:
i:
(n + 1).
j:{(i + 1)..(n + 1)
}. f i = f j
Applied Tactic: (OnMCls [1;2;0] ArithSimp ...a) THEN (Decide 
k:
n. f n = f k
...a)
Generated subgoals:1.
i:
(1 + n).
j:{(1 + i)..(1 + n)
}. f i = f j2.
i:
(1 + n).
j:{(1 + i)..(1 + n)
}. f i = f j