Ten prime numbers describing an arithmetic sequence

AI Thread Summary
The discussion centers on the existence of ten distinct prime numbers, each less than 3000, that can form an arithmetic sequence. A contradiction arises when analyzing the sums of these primes, specifically that the sum of the first two primes in the sequence equals the third term, which is mathematically inconsistent. Participants explore the number of runs of primes that can form sequences of different lengths, noting that there is only one run of length 10 among primes under 3000. Questions are raised about the conditions needed to find additional runs of length 10 and the longest possible runs of arithmetically sequenced primes below 1 million. The conversation highlights the challenges and nuances in identifying such sequences within specified numerical limits.
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Ten distinct prime numbers, each less than 3000, when arranged in increasing order of magnitude describe an arithmetic sequence.

What are these ten prime numbers?
 
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wrong
 
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Jarle said:
But the sum of the prime numbers p and p+d are even, but also equal to the prime number p+3d, a contradiction.

Why p+p+d = p+3d ?
 
199 + n * 210 (where n = 0, 1, 2, ..., 9) are all primes.
I found this by brute force. Here's an easy question. This is a run of length 10. There are two runs of length 9. What are they?
 
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jimmysnyder said:
Here's an easy question. This is a run of length 10. There are two runs of length 9. What are they?

Are you implying that there are more runs of 9 besides the 2 included within your run of 10?

But while we're doing brute force:
There's only 1 run of length 10 within all the primes up to a max of 3000. But how high do you have to push the max before you find another run of 10? How many runs of 10 are there with all the primes below 1 million?

DaveE
 
Jarle said:
They are on the form p,p+d,p+2d..., where p is an odd prime and d is a positive integer. But the sum of the prime numbers p and p+d are even, but also equal to the prime number p+3d, a contradiction.

p + p + d =/= p + d+d+d simple mistake
 
davee123 said:
Are you implying that there are more runs of 9 besides the 2 included within your run of 10?
This isn't jeopardy. Pose your answer in the form of an answer.
 
jimmysnyder said:
This isn't jeopardy. Pose your answer in the form of an answer.

Ok, just checking.

And another brute forcer: what's the longest run of arithmetically sequenced primes below 1 million?

DaveE
 
So, just so I don't leave these questions without answers:

There's only 1 run of length 10 within all the primes up to a max of 3000. But how high do you have to push the max before you find another run of 10?

53813

How many runs of 10 are there with all the primes below 1 million?

144

What's the longest run of arithmetically sequenced primes below 1 million?

The longest run is 15 primes

DaveE
 
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