Help plz

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I mouseslipped again... https://www.chess.com/votechess/game/206021 nobody is perfect. Only certain numbers.

A perfect number is a number where the sum of its factors (excluding itself) adds to be the number itself. Perfect numbers are VERY rare, and I only remember the first 4.

6: 1+2+3=6

28: 1+2+4+7+14=28

496: 1+2+4+8+16+31+62+124+248=496

8128: 1+2+4+8+16+32+64+127+254+508+1016+2032+4064=8128

Don't believe me on the last one? Use the calculator!

Look at the two middle factors. 

We can express any perfect number as 2^(n-1)*2^n-1, as long as 2^n-1 is a prime. In order for it to be prime, n must first be a prime. Numbers like 2^n-1 that's a prime is also known as a Mersenne prime. 

List of Mersenne Primes (For 13 numbers): <-- Not a sad face

n|(2^n-1)

1|1 (nope)

2|3 (yep)

3|7 (yep)

4|15 (nope, 3*5)

5|31 (yep)

6|63 (nope, 3^2*7)

7|127 (yep)

8|255 (nope, 3*5*17)

9|511 (nope, 7*73)

10|1023 (nope, 3*11*31)

11|2047 (nope, 23*89)

Wait! Our pattern is broken! I thought as long as n was prime, 2^n-1 is also prime!

Well, what I was trying to say was in order for 2^n-1 to be a Mersenne prime, n must be prime, but even if n is prime, it is not guaranteed 2^n-1 is prime.

12|4095 (nope, 3^2*5*7*13)

13|8191 (yep)

so the next perfect number after that is 4096*8191 ( @Penguin4096 it's 4096 be happy like the number itself). For the record, that is 33550336. These numbers get real big, real fast! wink.png

Anyways, may you please join the votechess https://www.chess.com/votechess/game/206021 (I would play Nc5)

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225th in Votechess!

225th in Votechess!