1971:
1: 1^97*1
2: 1^97+1
3: 1*9-7+1
4: 1+9-7+1
5: -1^9+7-1
6: 1^9*7-1
7: 1^9+7-1 or 1^9*7*1
8: 1^9+7*1
9: 1^9+7+1
10: 1*sqrt(9)+7*1
11: 1*sqrt(9)+7+1
12: 1+sqrt(9)+7+1
13: (-1+sqrt(9))*7-1 or 1 + (sqrt(9))! + 7 - 1
14: 1 + (sqrt(9))! + 7 * 1 or -1+9+7-1
15: 1 + (sqrt(9))! + 7 + 1 or 1*9+7-1
16: 1*9+7*1
17: 1*9+7+1
18: 1+9+7+1
19: -1+(sqrt(9))*7-1
20: 1*(sqrt(9))*7-1
21: 1*(sqrt(9))*7*1
22: 1*(sqrt(9))*7+1
23: 1+(sqrt(9))*7+1
24: 1*(sqrt(9))*(7+1)
25: 1+(sqrt(9))*(7+1)
26: 19+7*1 or 1+(-sqrt(9)+7)!+1
27: (1*sqrt(9))*7-1
28: (1*sqrt(9))*7*1
29: (1*sqrt(9))*7+1
30: (-1+(sqrt(9))!)*(7-1)
31: (1+sqrt(9))!+7*1
32: (1+sqrt(9))*(7+1)
33:
34: (-1+(sqrt(9))!)*7-1
35: (-1+(sqrt(9))!)*7*1
36: (-1+(sqrt(9))!)*7+1 or (1*sqrt(9)!) * (7-1)
37: 1 + (sqrt(9)!) * (7-1)