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nat prime div each factorLEMMA1112111 1. X : 2. prime(X)
3. X1:. X1<X prime(X1) (a,b:. X1 | abX1 | aX1 | b)
4. W : 5. W1:. W1<W 0<W1W1<X (t:. X | tW1X | t)
6. 0<W 7. W<X 8. t : 9. u : 10. tW = Xu 11. W = 1
12. X1 : {2...}
13. X1W 14. prime(X1)
15. c : 16. W = X1c 17. tX1c = Xu X | t