Home / Riddles / Logic riddles / What Letter Comes Next: O, T, T, F, F, S, S, E?
Logic riddles
What letter comes next: O, T, T, F, F, S, S, E…?
A sequence puzzle that looks like a cipher. The letters follow a rule you have known since kindergarten, which is exactly why it is hard to see.
What letter comes next: O, T, T, F, F, S, S, E…?
Hint: Count out loud.
Reveal the answer
N
They are the first letters of One, Two, Three… Eight, so next is N for Nine.
How to solve it (spoilers)
How to think about it
- Look for a pattern in the letters themselves: O, T, T, F, F, S, S, E. Pairs of repeated letters suggest they stand for words that begin the same way.
- The hint says to count out loud. Say the counting numbers and listen to their first letters.
- One, Two, Three, Four, Five, Six, Seven, Eight: O, T, T, F, F, S, S, E. The pattern matches perfectly.
- The next number is Nine, so the next letter is N.
Why “N” is the answer
The sequence lists the first letter of each counting word from one to eight, so the next entry is the first letter of nine, which is N. The puzzle disguises an ordinary count as a mysterious code. Once you read the letters as initials, the whole series falls into place and you can extend it as far as you like: N, T, E, T…
Common wrong answers
- T. T would fit if the letters were an alphabet-based pattern, but they are initials of number words and the next word is nine.
- S. S appears twice already for six and seven; nine does not start with S.
Related riddles
- What comes once in a minute, twice in a moment, but never in a thousand years?
- What starts with an E, ends with an E, but usually contains only one letter?
- I am an odd number. Take away one letter and I become even. What number am I?
- What four-letter word reads the same forward, backward and upside down?
- What comes next: 1, 1, 2, 3, 5, 8, 13…?
Want a fresh one every week? Try the riddle of the week.