How Large Are Mersenne Primes in Decimal Digits?

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Discussion Overview

The discussion centers around estimating the number of decimal digits in a Mersenne prime, specifically the number represented by 2^(216091) - 1. Participants explore methods for calculating this estimate without the use of calculus.

Discussion Character

  • Homework-related, Mathematical reasoning, Debate/contested

Main Points Raised

  • One participant defines a Mersenne prime and provides an example, suggesting that 2^(216091) - 1 is a large Mersenne prime.
  • Another participant proposes an equation, 2^(216091) = 10^x, to estimate the number of decimal digits, indicating that the -1 can be ignored for the estimation.
  • A third participant clarifies that the problem is a challenge rather than homework, asserting they have an answer of 72030.
  • A later reply challenges the correctness of the provided answer, suggesting that there may have been an error in the calculations.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correct number of decimal digits, with differing opinions on the accuracy of the proposed answer and the method of estimation.

Contextual Notes

Participants have not fully resolved the mathematical steps involved in estimating the number of decimal digits, and there is uncertainty regarding the significance of the -1 in the context of the estimation.

anil
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A prime number is a positive ineger greater than 2 whose only integer divisors are itself and 1. A Mersenne prime in of the form 2^(n) - 1 where p is a prime. For example 2^(5) - 1 = 31 is a Mersenne prime. One of the larger Mersenne prime is 2^(216091) - 1. Estimate the number of decimal digits in this number.

Please post your explanation and your answer. No this problem needs no calculus. Got guts[?]
 
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Okay it's not my job to do your homework, so I will only give you a few pointers:

The -1 is unimortant to your estimate, so ignore that for the minute:

You can then construct this equation:

2^(216091) = 10^x

From here it should be very easy to solve.
 
Kiddo: this is not my HW

This is not my homework. LoL this is a "challenge problem" they give in my college to exercise brain. I got the answer I just want to see my asnwer is right. 72030
 
No your answer is wrong, look at the equation I gave again, you may of made a simple error.
 

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