let n be Nat; :: thesis: ( not n divides 325 or n = 1 or n = 5 or n = 13 or n = 25 or n = 65 or n = 325 )
assume n divides 325 ; :: thesis: ( n = 1 or n = 5 or n = 13 or n = 25 or n = 65 or n = 325 )
then n divides 13 * 25 ;
then consider a, b being Nat such that
A1: ( a divides 13 & b divides 25 ) and
A2: n = a * b by Lem1;
( ( a = 1 or a = 13 ) & ( b = 1 or b = 5 or b = 25 ) ) by A1, Th13, XPRIMES1:13;
hence ( n = 1 or n = 5 or n = 13 or n = 25 or n = 65 or n = 325 ) by A2; :: thesis: verum