Inspired by Ikkyu San
Calculus
Level
4
\[\large\dfrac { 1\cdot 2\cdot 3 }{ 1!+2!+3! } +\dfrac { 2\cdot 3\cdot 4 }{ 2!+3!+4! } +\dfrac { 3\cdot 4\cdot 5 }{ 3!+4!+5! }+\cdots = \, ? \]
\[ \] \[ \]
Notation:
\(!\) denotes the factorial notation. For example, \(8! = 1\times2\times3\times\cdots\times8 \).
by
Hamza A