# Sum of Reciprocals of Triangular Numbers

Sum of Reciprocals of Triangular Numbers

The sum of the reciprocals of the triangular numbers is

1

1

1

3

1

6

1

n+1 |

2 |

For each , the area of each colored rectangle in the graphic is .

n

1×-=

2

n

2

n+1

1

n+1 |

2 |