# Amicable Pair/Examples/59,554,936,495,441,481,044,788,091,271,148,664,944,796,300,859,243,635,311,219,048,448-59,554,936,495,441,891,385,123,332,422,108,719,776,971,992,921,810,832,072,976,105,472

## Example of Amicable Pair

$59 \, 554 \, 936 \, 495 \, 441 \, 481 \, 044 \, 788 \, 091 \, 271 \, 148 \, 664 \, 944 \, 796 \, 300 \, 859 \, 243 \, 635 \, 311 \, 219 \, 048 \, 448$

and

$59 \, 554 \, 936 \, 495 \, 441 \, 891 \, 385 \, 123 \, 332 \, 422 \, 108 \, 719 \, 776 \, 971 \, 992 \, 921 \, 810 \, 832 \, 072 \, 976 \, 105 \, 472$

are an amicable pair:

 $\displaystyle$  $\displaystyle \sigma \left({59 \, 554 \, 936 \, 495 \, 441 \, 481 \, 044 \, 788 \, 091 \, 271 \, 148 \, 664 \, 944 \, 796 \, 300 \, 859 \, 243 \, 635 \, 311 \, 219 \, 048 \, 448}\right)$ $\displaystyle$ $=$ $\displaystyle \sigma \left({59 \, 554 \, 936 \, 495 \, 441 \, 891 \, 385 \, 123 \, 332 \, 422 \, 108 \, 719 \, 776 \, 971 \, 992 \, 921 \, 810 \, 832 \, 072 \, 976 \, 105 \, 472}\right)$ $\displaystyle$ $=$ $\displaystyle 119 \, 109 \, 872 \, 990 \, 883 \, 372 \, 429 \, 911 \, 423 \, 693 \, 257 \, 384 \, 721 \, 768 \, 293 \, 781 \, 054 \, 467 \, 384 \, 195 \, 153 \, 920$ $\displaystyle$ $=$ $\displaystyle 59 \, 554 \, 936 \, 495 \, 441 \, 481 \, 044 \, 788 \, 091 \, 271 \, 148 \, 664 \, 944 \, 796 \, 300 \, 859 \, 243 \, 635 \, 311 \, 219 \, 048 \, 448$ $\displaystyle$  $\, \displaystyle + \,$ $\displaystyle 59 \, 554 \, 936 \, 495 \, 441 \, 891 \, 385 \, 123 \, 332 \, 422 \, 108 \, 719 \, 776 \, 971 \, 992 \, 921 \, 810 \, 832 \, 072 \, 976 \, 105 \, 472$

## Proof

By definition, $m$ and $n$ form an amicable pair if and only if:

$\sigma \left({m}\right) = \sigma \left({n}\right) = m + n$

where $\sigma \left({n}\right)$ denotes the $\sigma$ function.

 $\displaystyle$  $\displaystyle \sigma \left({59 \, 554 \, 936 \, 495 \, 441 \, 481 \, 044 \, 788 \, 091 \, 271 \, 148 \, 664 \, 944 \, 796 \, 300 \, 859 \, 243 \, 635 \, 311 \, 219 \, 048 \, 448}\right)$ $\displaystyle$ $=$ $\displaystyle 119 \, 109 \, 872 \, 990 \, 883 \, 372 \, 429 \, 911 \, 423 \, 693 \, 257 \, 384 \, 721 \, 768 \, 293 \, 781 \, 054 \, 467 \, 384 \, 195 \, 153 \, 920$
 $\displaystyle$  $\displaystyle \sigma \left({59 \, 554 \, 936 \, 495 \, 441 \, 891 \, 385 \, 123 \, 332 \, 422 \, 108 \, 719 \, 776 \, 971 \, 992 \, 921 \, 810 \, 832 \, 072 \, 976 \, 105 \, 472}\right)$ $\displaystyle$ $=$ $\displaystyle 119 \, 109 \, 872 \, 990 \, 883 \, 372 \, 429 \, 911 \, 423 \, 693 \, 257 \, 384 \, 721 \, 768 \, 293 \, 781 \, 054 \, 467 \, 384 \, 195 \, 153 \, 920$

while:

 $\displaystyle$ $=$ $\displaystyle 119 \, 109 \, 872 \, 990 \, 883 \, 372 \, 429 \, 911 \, 423 \, 693 \, 257 \, 384 \, 721 \, 768 \, 293 \, 781 \, 054 \, 467 \, 384 \, 195 \, 153 \, 920$ $\displaystyle$ $=$ $\displaystyle 59 \, 554 \, 936 \, 495 \, 441 \, 481 \, 044 \, 788 \, 091 \, 271 \, 148 \, 664 \, 944 \, 796 \, 300 \, 859 \, 243 \, 635 \, 311 \, 219 \, 048 \, 448$ $\displaystyle$  $\, \displaystyle + \,$ $\displaystyle 59 \, 554 \, 936 \, 495 \, 441 \, 891 \, 385 \, 123 \, 332 \, 422 \, 108 \, 719 \, 776 \, 971 \, 992 \, 921 \, 810 \, 832 \, 072 \, 976 \, 105 \, 472$

$\blacksquare$