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## #1 2013-12-30 18:19:08

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Prime Number Challenges

1. What is the 5th prime number, which is also an additive prime?
2. What is a Mersenne prime?

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I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #2 2013-12-30 18:22:20

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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## #3 2013-12-30 18:28:20

mathaholic
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From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

Easy, right? No scoreboard this time.

3. Complete the sequence: 3, 7, 13, 19, 29, __ , __

4. What is the perfect number that when you subtract 1 to it, you get a prime?

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #4 2013-12-30 18:37:55

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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## #5 2013-12-30 18:57:26

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

Yes.

5. What is the prime exponent of 5 wherein when added the digits of the number, you get a prime number (5^n = digit 1 + digit 2... = p)?

6. Which is the first twin triplet (3 consecutive twin primes)?

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #6 2014-01-02 16:54:41

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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## #7 2014-01-02 17:18:41

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

That was a tricky one!

7. Complete the digits:

8. Is 36+(9*12)-(11*(2+3) prime?

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #8 2014-01-02 17:26:10

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

I do not understand 7.

8 is missing a parentheses.

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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## #9 2014-01-02 17:28:19

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

Hint: On 7, it is the largest known prime.

For 8, whoops, sorry.

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #10 2014-01-02 17:32:19

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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## #11 2014-01-02 17:34:59

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

7. Yes.

8. The answer was 89. Good.

9. When counted the letters of mathaholic, is it prime or composite?

10. What is the first prime number from 201 - 300?

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #12 2014-01-02 18:02:03

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

For 9) the number of letters you want counted?

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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## #13 2014-01-02 18:10:06

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

Number of letters of my username, mathaholic.

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #14 2014-01-02 18:24:51

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

]

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

## #15 2014-01-02 18:35:06

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

11. Is this true? c + c = p

12. What is the 1,000,000th prime number?

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #16 2014-01-02 18:45:47

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

11) I do not understand the question.

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

## #17 2014-01-02 19:18:59

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

11. Composite number + Composite number = prime number

12. Good. Just 11

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #18 2014-01-02 22:26:58

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

## #19 2014-01-03 12:26:35

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

Sometimes it is false, too: 4 + 6 = 10, or 4 + 4 = 8

13. You might not be able to answer this: What is 13^13 - (13*(13th prime number)) ?

14. Let's ease it off a little. If 2 + 3 = 5, what is 3 + 5 ? Note: This is not literal addition.

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #20 2014-01-03 15:12:23

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

## #21 2014-01-03 15:59:33

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

13. Okay.

14. I actually made a puzzle of 1 + 4 = 9 = 4 + 9 = ?.

Now, look:

2 is the first prime number, and 3 is the second prime number. Add the orders, 1 + 2 = 3rd prime number = 5.

3 is the second prime number, and 5 is the third prime number. 2 + 3 = 5th prime number = 2, 3, 5, 7, 11.

15. What is the 17th prime number?

16. Square the 17th prime number, and what is it?

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #22 2014-01-03 16:06:31

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

## #23 2014-01-03 16:41:05

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

There are 2 answers for 16:

17[sup]2[/sup] = 289

The 289th prime number is 1,879

Another solution is what you did: 17p[sup]2[/sup]

17. What is the 5th prime number + the 5th prime number squared?

18. What is the 8th prime number + the 1st prime number cubed?

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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## #24 2014-01-03 16:54:54

bobbym
From: Bumpkinland
Registered: 2009-04-12
Posts: 92,930

### Re: Prime Number Challenges

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

## #25 2014-01-03 16:56:35

mathaholic
Member
From: idk
Registered: 2012-11-29
Posts: 2,905
Website

### Re: Prime Number Challenges

17. Good
18. Good

Bonus!

19 - 20. If 97 is the 25th prime number, is 199 the 50th prime number? If no, what is it?

I will have a name change soon. By the way, welcome to the Philippines, Pope Francis!

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