with the sum of numbers, and it can be used more than one time but not more than 9 times for all
in Calculus Answers by

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1 Answer

I started off by figuring how many ways to use nines:

30
  3 nines, 27 total
  2 nines, 18 total
  1 nine, 9 total
  0 nines, 0 total

I then figured how many ways to use sevens:

30
  3 nines, 27 total
    0 sevens, 27 total
  2 nines, 18 total
    1 seven, 25 total
    0 sevens, 18 total
  1 nine, 9 total
    3 sevens, 30 total
    2 sevens, 23 total
    1 seven, 16 total
    0 sevens, 9 total
  0 nines, 0 total
    4 sevens, 28 total
    3 sevens, 21 total
    2 sevens, 14 total
    1 seven, 7 total
    0 sevens, 0 total

I then figured how many ways to use fives, then threes, ending up with this:

30
  3 nines, 27 total
    0 sevens, 27 total
      0 fives, 27 total
        1 three, 30 total
        0 threes, 27 total
  2 nines, 18 total
    1 seven, 25 total
      1 five, 30 total
        0 threes, 30 total
      0 fives, 25 total
        1 three, 28 total
        0 threes, 25 total
    0 sevens, 18 total
      2 fives, 28 total
        0 threes, 28 total
      1 five, 23 total
        2 threes, 29 total
        1 three, 26 total
        0 threes, 23 total
      0 fives, 18 total
        4 threes, 30 total
        3 threes, 27 total
        2 threes, 24 total
        1 three, 21 total
        0 three, 18 total
  1 nine, 9 total
​    3 sevens, 30 total
      0 fives, 30 total
        0 threes, 30 total
    2 sevens, 23 total
      1 five, 28 total
        0 threes, 28 total
      0 fives, 23 total
        2 threes, 29 total
        1 three, 26 total
        0 threes, 23 total
    1 seven, 16 total
      2 fives, 26 total
        1 three, 29 total
        0 threes, 26 total
      1 five, 21 total
        3 threes, 30 total
        2 threes, 27 total
        1 three, 24 total
        0 threes, 21 total
      0 fives, 16 total
        4 threes, 28 total
        3 threes, 25 total
        2 threes, 22 total
        1 three, 19 total
    0 threes, 16 total
    0 sevens, 9 total
      4 fives, 29 total
    0 threes, 29 total
      3 fives, 24 total
    2 threes, 30 total
    1 three, 27 total
    0 threes, 24 total
      2 fives, 19 total
    3 threes, 28 total
    2 threes, 25 total
    1 three, 22 total
    0 threes, 19 total
      1 five, 14 total
    5 threes, 29 total
    4 threes, 26 total
        3 threes, 23 total
    2 threes, 20 total
    1 three, 17 total
    0 threes, 14 total
      0 fives, 9 total
    7 threes, 30 total
    6 threes, 27 total
    5 threes, 24 total
    4 threes, 21 total
    3 threes, 18 total
    2 threes, 15 total
    1 three, 12 total
    0 threes, 9 total
  0 nines, 0 total
    4 sevens, 28 total
      0 fives, 28 total
    0 threes, 28 total
    3 sevens, 21 total
      1 five, 26 total
    1 three, 29 total
    0 threes, 26 total
      0 fives, 21 total
    3 threes, 30 total
    2 threes, 27 total
    1 three, 24 total
    0 threes, 21 total
    2 sevens, 14 total
      3 fives, 29 total
    0 threes, 29 total
      2 fives, 24 total
    2 threes, 30 total
    1 three, 27 total
    0 threes, 24 total
      1 five, 19 total
    3 threes, 28 total
    2 threes, 25 total
    1 three, 22 total
    0 threes, 19 total
      0 fives, 14 total
    5 threes, 29 total
    4 threes, 26 total
    3 threes, 23 total
    2 threes, 20 total
    1 three, 17 total
    0 threes, 14 total
    1 seven, 7 total
      4 fives, 27 total
    1 three, 30 total
    0 threes, 27 total
      3 fives, 22 total
    2 threes, 28 total
    1 three, 25 total
    0 threes, 22 total
      2 fives, 17 total
    4 threes, 29 total
    3 threes, 26 total
    2 threes, 23 total
    1 three, 20 total
    0 threes, 17 total
      1 five, 12 total
    6 threes, 30 total
    5 threes, 27 total
    4 threes, 24 total
    3 threes, 21 total
    2 threes, 18 total
    1 three, 15 total
    0 threes, 12 total
      0 fives, 7 total
    7 threes, 28 total
    6 threes, 25 total
    5 threes, 22 total
    4 threes, 19 total
    3 threes, 16 total
    2 threes, 13 total
    1 three, 10 total
    0 threes, 7 total
    0 sevens, 0 total
      6 fives, 30 total
    0 threes, 30 total
      5 fives, 25 total
    1 three, 28 total
    0 threes, 25 total
      4 fives, 20 total
    3 threes, 29 total
    2 threes, 26 total
    1 three, 23 total
    0 threes, 20 total
      3 fives, 15 total
    5 threes, 30 total
    4 threes, 27 total
    3 threes, 24 total
    2 threes, 21 total
    1 three, 18 total
    0 threes, 15 total
      2 fives, 10 total
    6 threes, 28 total
    5 threes, 25 total
    4 threes, 22 total
    3 threes, 19 total
    2 threes, 16 total
    1 three, 13 total
    0 threes, 10 total
      1 five, 5 total
    8 threes, 29 total
    7 threes, 26 total
    6 threes, 23 total
    5 threes, 20 total
    4 threes, 17 total
    3 threes, 14 total
    2 threes, 11 total
    1 three, 8 total
    0 threes, 5 total
      0 fives, 0 total
    10 threes, 30 total
    9 threes, 27 total
    8 threes, 24 total
    7 threes, 21 total
    6 threes, 18 total
    5 threes, 15 total
    4 threes, 12 total
    3 threes, 9 total
    2 threes, 6 total
    1 three, 3 total
    0 threes, 0 total

(more to follow)
by Level 13 User (103k points)
We have to remove the line with 0 nines, 0 sevens, 0 fives and 10 threes because we're not allowed to use more than 9 of each number.

For each line that looks like 'x threes, y total' the remaining amount (if any) has to be made up of ones.  But, since we're not allowed to use more than 9 ones, anything that says 'x threes, y total' with y less than 21 can't be used because it would require more than 9 ones.  Here's the above list, but with any y number less than 21 removed:

30
  3 nines, 27 total
    0 sevens, 27 total
      0 fives, 27 total
        1 three, 30 total
        0 threes, 27 total
  2 nines, 18 total
    1 seven, 25 total
      1 five, 30 total
        0 threes, 30 total
      0 fives, 25 total
        1 three, 28 total
        0 threes, 25 total
    0 sevens, 18 total
      2 fives, 28 total
        0 threes, 28 total
      1 five, 23 total
        2 threes, 29 total
        1 three, 26 total
        0 threes, 23 total
      0 fives, 18 total
        4 threes, 30 total
        3 threes, 27 total
        2 threes, 24 total
        1 three, 21 total
  1 nine, 9 total
​    3 sevens, 30 total
      0 fives, 30 total
        0 threes, 30 total
    2 sevens, 23 total
      1 five, 28 total
        0 threes, 28 total
      0 fives, 23 total
        2 threes, 29 total
        1 three, 26 total
        0 threes, 23 total
    1 seven, 16 total
      2 fives, 26 total
        1 three, 29 total
        0 threes, 26 total
      1 five, 21 total
        3 threes, 30 total
        2 threes, 27 total
        1 three, 24 total
        0 threes, 21 total
      0 fives, 16 total
        4 threes, 28 total
        3 threes, 25 total
        2 threes, 22 total
    0 sevens, 9 total
      4 fives, 29 total
    0 threes, 29 total
      3 fives, 24 total
    2 threes, 30 total
    1 three, 27 total
    0 threes, 24 total
      2 fives, 19 total
    3 threes, 28 total
    2 threes, 25 total
    1 three, 22 total
      1 five, 14 total
    5 threes, 29 total
    4 threes, 26 total
        3 threes, 23 total
      0 fives, 9 total
    7 threes, 30 total
    6 threes, 27 total
    5 threes, 24 total
    4 threes, 21 total
  0 nines, 0 total
    4 sevens, 28 total
      0 fives, 28 total
    0 threes, 28 total
    3 sevens, 21 total
      1 five, 26 total
    1 three, 29 total
    0 threes, 26 total
      0 fives, 21 total
    3 threes, 30 total
    2 threes, 27 total
    1 three, 24 total
    0 threes, 21 total
    2 sevens, 14 total
      3 fives, 29 total
    0 threes, 29 total
      2 fives, 24 total
    2 threes, 30 total
    1 three, 27 total
    0 threes, 24 total
      1 five, 19 total
    3 threes, 28 total
    2 threes, 25 total
    1 three, 22 total
      0 fives, 14 total
    5 threes, 29 total
    4 threes, 26 total
    3 threes, 23 total
    1 seven, 7 total
      4 fives, 27 total
    1 three, 30 total
    0 threes, 27 total
      3 fives, 22 total
    2 threes, 28 total
    1 three, 25 total
    0 threes, 22 total
      2 fives, 17 total
    4 threes, 29 total
    3 threes, 26 total
    2 threes, 23 total
      1 five, 12 total
    6 threes, 30 total
    5 threes, 27 total
    4 threes, 24 total
    3 threes, 21 total
      0 fives, 7 total
    7 threes, 28 total
    6 threes, 25 total
    5 threes, 22 total
    0 sevens, 0 total
      6 fives, 30 total
    0 threes, 30 total
      5 fives, 25 total
    1 three, 28 total
    0 threes, 25 total
      4 fives, 20 total
    3 threes, 29 total
    2 threes, 26 total
    1 three, 23 total
      3 fives, 15 total
    5 threes, 30 total
    4 threes, 27 total
    3 threes, 24 total
    2 threes, 21 total
      2 fives, 10 total
    6 threes, 28 total
    5 threes, 25 total
    4 threes, 22 total
      1 five, 5 total
    8 threes, 29 total
    7 threes, 26 total
    6 threes, 23 total
      0 fives, 0 total
    9 threes, 27 total
    8 threes, 24 total
    7 threes, 21 total
This gives us a list of all possible solutions (92 of them):

9 + 9 + 9 + 3
9 + 9 + 9 + 1 + 1 + 1
9 + 9 + 7 + 5
9 + 9 + 7 + 3 + 1 + 1
9 + 9 + 7 + 1 + 1 + 1 + 1 + 1
9 + 9 + 5 + 5 + 1 + 1
9 + 9 + 5 + 3 + 3 + 1
9 + 9 + 5 + 3 + 1 + 1 + 1 + 1
9 + 9 + 5 + 1 + 1 + 1 + 1 + 1 + 1 + 1
9 + 9 + 3 + 3 + 3 + 3

9 + 9 + 3 + 3 + 3 + 1 + 1 + 1
9 + 9 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1
9 + 9 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
9 + 7 + 7 + 7
9 + 7 + 7 + 5 + 1 + 1
9 + 7 + 7 + 3 + 3 + 1
9 + 7 + 7 + 3 + 1 + 1 + 1 + 1
9 + 7 + 7 + 1 + 1 + 1 + 1 + 1 + 1 + 1
9 + 7 + 5 + 5 + 3 + 1
9 + 7 + 5 + 5 + 1 + 1 + 1 + 1

9 + 7 + 5 + 3 + 3 + 3
9 + 7 + 5 + 3 + 3 + 1 + 1 + 1
9 + 7 + 5 + 3 + 1 + 1 + 1 + 1 + 1 + 1
9 + 7 + 5 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
9 + 7 + 3 + 3 + 3 + 3 + 1 + 1
9 + 7 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1
9 + 7 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
9 + 5 + 5 + 5 + 5 + 1
9 + 5 + 5 + 5 + 3 + 3
9 + 5 + 5 + 5 + 3 + 1 + 1 + 1

9 + 5 + 5 + 5 + 1 + 1 + 1 + 1 + 1 + 1
9 + 5 + 5 + 3 + 3 + 3 + 1 + 1
9 + 5 + 5 + 3 + 3 + 1 + 1 + 1 + 1 + 1
9 + 5 + 5 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
9 + 5 + 3 + 3 + 3 + 3 + 3 + 1
9 + 5 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1
9 + 5 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1
9 + 3 + 3 + 3 + 3 + 3 + 3 + 3
9 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1
9 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1

9 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
7 + 7 + 7 + 7 + 1 + 1
7 + 7 + 7 + 5 + 3 + 1
7 + 7 + 7 + 5 + 1 + 1 + 1 + 1
7 + 7 + 7 + 3 + 3 + 3
7 + 7 + 7 + 3 + 3 + 1 + 1 + 1
7 + 7 + 7 + 3 + 1 + 1 + 1 + 1 + 1 + 1
7 + 7 + 7 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
7 + 7 + 5 + 5 + 5 + 1
7 + 7 + 5 + 5 + 3 + 3

7 + 7 + 5 + 5 + 3 + 1 + 1 + 1
7 + 7 + 5 + 5 + 1 + 1 + 1 + 1 + 1 + 1
7 + 7 + 5 + 3 + 3 + 3 + 1 + 1
7 + 7 + 5 + 3 + 3 + 1 + 1 + 1 + 1 + 1
7 + 7 + 5 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
7 + 7 + 3 + 3 + 3 + 3 + 3 + 1
7 + 7 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1
7 + 7 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1
7 + 5 + 5 + 5 + 5 + 3
7 + 5 + 5 + 5 + 5 + 1 + 1 + 1

7 + 5 + 5 + 5 + 3 + 3 + 1 + 1
7 + 5 + 5 + 5 + 3 + 1 + 1 + 1 + 1 + 1
7 + 5 + 5 + 5 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
7 + 5 + 5 + 3 + 3 + 3 + 3 + 1
7 + 5 + 5 + 3 + 3 + 3 + 1 + 1 + 1 + 1
7 + 5 + 5 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1
7 + 5 + 3 + 3 + 3 + 3 + 3 + 3
7 + 5 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1
7 + 5 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1
7 + 5 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1

7 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1
7 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1
7 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
5 + 5 + 5 + 5 + 5 + 5
5 + 5 + 5 + 5 + 5 + 3 + 1 + 1
5 + 5 + 5 + 5 + 5 + 1 + 1 + 1 + 1 + 1
5 + 5 + 5 + 5 + 3 + 3 + 3 + 1
5 + 5 + 5 + 5 + 3 + 3 + 1 + 1 + 1 + 1
5 + 5 + 5 + 5 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1
5 + 5 + 5 + 3 + 3 + 3 + 3 + 3

5 + 5 + 5 + 3 + 3 + 3 + 3 + 1 + 1 + 1
5 + 5 + 5 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1
5 + 5 + 5 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
5 + 5 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1
5 + 5 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1
5 + 5 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1
5 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 1
5 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1
5 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1
3 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1

3 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1
3 + 3 + 3 + 3 + 3 + 3 + 3 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1

P.S.  I apologize- I am very well aware of the social faux pas of responding to my own post.  I had to do it this way due the length of the solution above.

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