sqrt{n+sqrt{(n-1)+sqrt{(n-2)+dotsb+sqrt{2+sqrt{1}}}}}

documentclass{article}
usepackage{amsmath}
usepackage{amssymb}
usepackage{yhmath}
begin{document}
  [ sqrt{n+sqrt{(n-1)+sqrt{(n-2)+dotsb+sqrt{2+sqrt{1}}}}}<sqrt{n}+1. ]
  [ wideparen{AB} ]
end{document}

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Package: yhmath
symyhlargesymbols=mathgroup6
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("C:Program FilesMiKTeX 2.9texlatexyhmathyhmath.sty"
Package: yhmath
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