Mersenne Prime (Probably) Discovered #42

A new Mersenne Prime number has been found by a group calling themselves Great Internet Mersenne Prime Search (GIMPS)

Mersenne numbers are numbers of the form M_n= 2ⁿ – 1.

They haven’t released the number yet, but it’s said to be the largest prime number ever discovered. The previous largest is #41st which is 7,235,733 digits! 2^24036583 -1

To put that in perspective, if you were to open MS Word, remove margins, change the font size to 8 Courier New and fill up the entire page, it would take 654 pages! (11,049 digits/page)

What I don’t understand is WHY!? Why would you want this number. There are no useful applications of this! If you can think of one, please comment.

Original Article

Trying to calculate these in Excel can only do the first 8 accurately, and #15 and above gives a #NUM error.
1. 2²-1 = 3
2. 2³-1 = 7
3. 2⁵-1 = 31
4. 2⁷-1 = 127
5. 2¹³-1 = 8191
6. 2¹⁷-1 = 131071
7. 2¹⁹-1 = 524287
8. 2³¹-1 = 2147483647
9. 2⁶¹-1 = 2.30584E+18
10. 2⁸⁹-1 = 6.1897E+26
11. 2¹⁰⁷-1 = 1.62259E+32
12. 2¹²⁷-1 = 1.70141E+38
13. 2⁵²¹-1 = 6.8648E+156
14. 2⁶⁰⁷-1 = 5.3114E+182
15. 2¹²⁷⁹-1 = #NUM!