# TI-82: Distinguishable Permutations

It is possible to find distinguishable permutations using the TI-82 calculator. Place the frequency
of each distinguishable item into a list - the following assumes List 1.

(sum L1)! / prod (L1!)

## Examples:

Find the number of distinguishable permutations of the letters in the word
"MISSISSIPPI".

**Letter** |
**Frequency** |

M |
1 |

I |
4 |

S |
4 |

P |
2 |

**Total** |
**11** |

The value, calculated by hand is: 11! / (1! * 4! * 4! * 2!) = 34650

On the calculator, List 1 would be {1,4,4,2}, and then run the above command.