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You wrote letters on the keyboard in tetrahedral sequence. This is 274th level of boredom. First sequence is just ones : 1 1 1 1 1 1... Second sequence is natural numbers : 1 2 3 4 5 6. You make next number by adding 1 Third sequence is triangular numbers : 1 3 6 10 15 21. You make nth number by adding n Fourth sequence is tetrahedral numbers : 1 4 10 20 35 56. You make nth number by adding nth number from the previous sequence. Same for next sequences. And for previous. You can find these sequences in Pascal's triangle and in (a+b) to the power of n.
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