Four Fours Puzzle - Solution

The Puzzle:

Four Fours
A popular mathematical pastime:

Use exactly four 4's to form every integer from 0 to 50, using only the operators +, -, x, /, () (brackets) x2 (square), and ! (factorial).

Example: 0 = 44-44




Our Solution:

0 = 44-44
1 = 44/44 or (4+4)/(4+4) or (4/4) / (4/4) or [(4! - 4)/ 4] - 4
2 = 4/4+4/4 or (42-4-4)/4
3 = (4+4+4)/4
4 = 4*(4-4)+4
5 = (4*4+4)/4
6 = 4*.4+4.4
7 = 44/4-4
8 = 4+4.4-.4
9 = 4/4+4+4
10 = 44/4.4
11 = 4/.4+4/4
12 = (44+4)/4
13 = 4!-44/4
14 = 4*(4-.4)-.4
15 = 44/4+4
16 = .4*(44-4)
17 = 4/4+4*4
18 = 44*.4+.4
19 = 4!-4-4/4
20 = 4*(4/4+4)
21 = (4.4+4)/.4
22 = 44*sqrt(4)/4
23 = (4*4!-4)/4
24 = 4*4+4+4
25 = (4*4!+4)/4
26 = 4/.4+4*4
27 = 4-4/4+4!
28 = 44-4*4
29 = 4/.4/.4+4
30 = (4+4+4)/.4
31 = (4!+4)/4+4!
32 = 4*4+4*4
33 = (4-.4)/.4+4!
34 = 44-4/.4
35 = 44/4+4!
36 = 44-4-4
37 = (sqrt(4)+4!)/sqrt(4)+4!
38 = 44-4!/4
39 = (4*4-.4)/.4
40 = 44-sqrt(4*4)
41 = (sqrt(4)+4!)/.4-4!
42 = sqrt(4)+44-4
43 = 44-4/4
44 = 44.4-.4
45 = 4/4+44
46 = 44-sqrt(4)+4
47 = 4!+4!-4/4
48 = 4*(4+4+4)
49 = (4!-4.4)/.4
50 = 4!/4+44

(Note: people have managed to do this for 1000s of numbers!)


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