## Challenge #3

It’s been a little while since my last post… I plead spring break vacation. At any rate, hopefully you figured out that the last post was intended as an April Fool’s joke. I hope you didn’t embarass yourself too badly trying to guess random numbers. (=

Here are some number sequences. Can you figure out the pattern and give the next three terms for each? (Each sequence follows a different pattern.)

1. $1, 3, 7, 15, 31, \dots$
2. $2, 5, 14, 41, 122, \dots$
3. $2, 6, 12, 20, 30, \dots$
4. $349, 32, 10, 2, 4, \dots$

Assistant Professor of Computer Science at Hendrix College. Functional programmer, mathematician, teacher, pianist, follower of Jesus.
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### 2 Responses to Challenge #3

1. Loweeel says:

note: square brackets indicate positions/subscripts.

1. 63, 127, 255. Pattern: [n+1] = 2n+1
2. 365, 1094, 3281. Pattern: [n+1] = 3n-1
3. 42, 56, 72. Pattern: [n+1] = n+([order in sequence of # n+1]*2)
4. Don’t want to try 😀

2. Laura says:

4. Add the digits together and double the result. So 8, 16, 14.