Unreachable numbers
C_K_Yang liuguangxi a_forsteri Burloq eulerscheZahl C3PO Philippe_57721 gerrob zilet sinan lesnik7 clytorock
Public  07/15/16  7xp  Programming  66.7% 
Using four numbers 4 and the 4 operations +, , *, / we can build all numbers up to 9.
With four numbers 5
What are the first unreachable numbers when we use eight 4 and eight 5?
Answer format: $u_4,u_5 $
Example: 10,8
[My timing: 40 sec]
 1 = ((4 + 4)  4) / 4
 2 = (4 / (4 + 4)) * 4
 3 = ((4 + 4) + 4) / 4
 4 = ((4  4) * 4) + 4
 5 = ((4 * 4) + 4) / 4
 6 = ((4 + 4) / 4) + 4
 7 = (4  (4 / 4)) + 4
 8 = ((4 + 4) + 4)  4
 9 = ((4 / 4) + 4) + 4
 12 = (4  (4 / 4)) * 4
With four numbers 5
 1 = ((5 + 5)  5) / 5
 2 = (5 / 5) + (5 / 5)
 3 = ((5 + 5) + 5) / 5
 4 = ((5 * 5)  5) / 5
 5 = ((5  5) * 5) + 5
 6 = ((5 * 5) + 5) / 5
 7 = ((5 + 5) / 5) + 5
 9 = (5  (5 / 5)) + 5
What are the first unreachable numbers when we use eight 4 and eight 5?
Answer format: $u_4,u_5 $
Example: 10,8
[My timing: 40 sec]
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