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3 remarkable numbers


Mike_F
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Yes, it turns out that the answer is Googlable... I like to call these "factorially self-referential" numbers, in that they refer to their own prime factors:

14 = 1st prime x 4th prime

154 = 1st prime x 5th prime x 4th prime

1196 = 1st x 1st x 9th x 6th

2127 = 2nd x 127th

61411 = 61st x 4th x 11th

66079 = 6th x 6th x 7th x 9th

172482 = 1st x 7th x 24th x 8th x 2nd

223227 = 2nd x 232nd x 2nd x 7th

279174 = 2nd x 7th x 9th x 1st x 7th x 4th

291318 = 2nd x 9th x 1st x 318th

 

I think this is it for integers below 1 million. Perhaps others will want to look for more -- or just let this bit of silliness stop...

 

 

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The puzzle is interesting, especially for those who are into number theory.

Last week I looked at this puzzle and decided I would not be able to find the connection among the numbers. So I searched OEIS out of curiosity. For some reason I didn't find it. (Strange.) Next I Googled the numbers themselves, and that turned up the football reference.

<moderator hat on>

I agree with Mike's sentiments. The Forum is for solving puzzles; it's not an Internet scavenger hunt. If you can't solve it, say so and maybe start a (spoilered) group effort. Or ask the OP for a clue.

The spoiler function permits multiple users to have a go at solving a puzzle. So solutions belong there. (Even funny ones about football.)

<moderator hat off>

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It can be argued that 2, 3, 5, and 7 are members of the sequence. Where the decimal expansion of n is 1, k = 1, and thus the number remains simply the prime. The integer sequence A097227 should, with the exclusion of these terms, state that the there are a minimum of two digits in each term, i.e., k > 1. Though the OEIS tries to be thoroughly correct, it is not always.

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