3.
已知数列\(\left\{ {{a}_{n}} \right\}\)中,\({{a}_{1}}=1\)且\({{a}_{n+1}}={{a}_{n}}+2n+1\),设数列\(\left\{ {{b}_{n}} \right\}\)满足\({{b}_{n}}={{a}_{n}}-1\),对任意正整数\(n\),不等式\(\dfrac{1}{{{b}_{2}}}+\dfrac{1}{{{b}_{3}}}+\bullet \bullet \bullet +\dfrac{1}{{{b}_{n}}} < m\)均成立,则实数\(m\)的取值范围为 .