14. (15 points) On the blackboard, there are 5 natural numbers: 1, 3, 5, 7, 9. One operation involves arbitrarily selecting two numbers from the blackboard, erasing them, and writing their sum on the blackboard, while writing their product on a piece of paper. After 4 such operations, there is only 1 number left on the blackboard, and 4 numbers are written on the paper. Find the sum of these 4 numbers.
【Analysis】The most basic method is to start from the 1st and 2nd numbers, erase the two numbers, and write down the sum of these two numbers minus 1, and the number written should be placed in the position of the 1st number. This process is repeated until only one number remains on the blackboard, which allows us to calculate the answer.

【Solution】Since it involves any two numbers, let's actually perform the operation with $1, 3, 5, 7, 9$:
- Erase $1, 3$; the blackboard now has: $4, 5, 7, 9$. Paper: 3
- Erase 4, 5; the blackboard now has: 9, 7, 9. Paper: $3, 20$
- Erase 9, 7; the blackboard now has: 16, 9. Paper: 3, 20, 63
- Erase 16, 9; the blackboard now has: 25. Paper: 3, 20, 63, 144
Thus, the sum of the four numbers on the paper is: $3+20+63+144=230$.
Answer: The sum of the four numbers is 230.