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Wheat Wizard
Wheat Wizard
23:50
30
Q: Number triangle flip

xnorSay you list the positive integers in a triangle, then flip it left-to-right. Given a number, output the number it's sent to. This is a self-inverse mapping. 1 1 2 3 3 2 4 5 6 <---> 6 5 4 7 8 ...

code-golf math sequence
I haven't seen any other Haskell golfer's on this question. Can anyone beat 34 bytes?

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