1. (S v T) > (S > ~T)
2. (S > ~T) > (T > K)
3. S v T
/ S v K
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4. S > ~T 1,3 Modus Ponens
5. T > K 2,4 Modus Ponens
6. ~~S v T 3 Double Negation
7. ~S > T 6 Material Implication
8. ~S > K 7,5 Hypothetical Syllogism
9. ~~S v K 8 Material Implication
10. S v K 9 Double Negation
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