# Is there a name for a formula to calculate ascending numbers to a quadratic-like sequence?

For e.g. any range of number 0 - n

0 1 2 3 4 5 6

to:

0 2 4 6 4 2 0

Is there a name for this kind of formula or calculation?

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Would you clarify the mapping? –  Charles Sep 2 '11 at 17:58
Sorry Charles, I do not know the mapping too, that's what I want to find out as well. –  yzyzyz Sep 2 '11 at 18:04

The tent map. In your case it'd be scaled to $f(x) = 2 \min(x, 6-x)$.