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# Letters

## Question

Here's another one of my favorites. Look at this sequence of letters and then tell us what the last letter should be.

O T T F F S S ___ ?????

Again, this is one my dad tried on me when I was about 10. He informed me that only a genius can figure it out in virtually no time. Well, I never claimed to be a genius, but I read off the letters and in perfect time I said the last letter.

Do I have to put the answer in here? I want to see how long it takes for anyone to answer it correctly.

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Here's another one of my favorites. Look at this sequence of letters and then tell us what the last letter should be.

O T T F F S S ___ ?????

Again, this is one my dad tried on me when I was about 10. He informed me that only a genius can figure it out in virtually no time. Well, I never claimed to be a genius, but I read off the letters and in perfect time I said the last letter.

Do I have to put the answer in here? I want to see how long it takes for anyone to answer it correctly.

I know I am late to this, but I have a mathematical solution to this. It is Y. The problem is an incremental sequence and repeat pattern problem. Think of the alphabet as an never ending circle. Thus after Z you start with A again, over and over again forever. You divide the letters into pairs and then you calculate the distance between the first letter in a pair with the second letter in the pair using the curricular alphabet. So O is 5 letters before T, and T is 12 letters before F. The first letter in the next pair always starts with the last letter of the previous pair and so on: O T / T F / F S / S?

The number sequencing pattern is: 5 & 12, then you flip it and add one to each number and get 13 & 6, then flip again and add one once more to each number to get 7 & 14, flip again and add one again to each number and get 15 & 8, and so on and so forth. That is how you find the second letter in each pair.

For this to be valid, you have to diverge down the levels till you have the same number over and over, OR a repeating pattern that never changes. So the last level being all sixes proves the solution.

I forget what this mathematical type of sequencing is called, but I learned it in a class on the nature of numbers in collage.

Cool, but the solution you guys came up with is very elegant. My hat is off to you.

Lilu

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The next three would be E, N, T. <_<

I got E immediatly, it just makes sense to be E, i'm definately no genius. I read your post and it's true the next letter is E

For those who cant see

One Two Three Four Five Six Seven Eight

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the next letters are E N T E T T F F S...... should i go on?

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