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Is there a function or anything else that gives the same result on a set?
I want to know if there is a function, for example, that gives the same result on the interval $[10,15]$. I want to have these function values
$f(10)=25,\, f(11)=25,\, f(12)=25,\, f(13)=25,\, f(14)=25,\, f(15)=25$
Thanks.