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[parent] examples of ranges of consecutive integers for Erdős-Woods numbers (Example)

The most famous example of 16 as an Erdos-Woods number is the range of 16 consecutive integers starting with 2184.

Another $n$ for $k = 16$ is 2044224, which we obtained by multiplying 2184 by 936. The factorization is $2044224 = 2^6 \times 3^3 \times 7 \times 13^2$ while $2044224 + 16 = 2044240 = 2^4 \times 5 \times 11 \times 23 \times 101$ The table of factorizations

2044225 $5^2 \times 81769$
2044226 $2 \times 1022113$
2044227 $3 \times 681409$
2044228 $2^2 \times 511057$
2044229 $11 \times 19 \times 9781$
2044230 $2 \times 3 \times 5 \times 68141$
2044231 $7^2 \times 41719$
2044232 $2^3 \times 59 \times 61 \times 71$
2044233 $3^2 \times 17 \times 31 \times 431$
2044234 $2 \times 1009 \times 1013$
2044235 $5 \times 107 \times 3821$
2044236 $2^2 \times 3 \times 170353$
2044237 $13 \times 67 \times 2347$
2044238 $2 \times 7 \times 151 \times 967$
2044239 $3 \times 29 \times 23497$

shows that each of the numbers in this range shares at least one factor with one if not both of the numbers capping the range.

Next we have a slightly longer example, this one for $k = 34$ The smallest matching $n$ is 47563752566, a squarefree number with a factorization of $2 \times 11 \times 17 \times 23 \times 41 \times 157 \times 859$ The number capping the end of the range is the decidedly non-squarefree 47563752600, with a factorization of $2^3 \times 3^2 \times 5^2 \times 7 \times 13 \times 17 \times 19 \times 29 \times 31$ While the size of these numbers forbids verification on your typical pocket calculator, these numbers are well within the reach of a Javascript implementation of trial division. Here we could be tempted to omit the even numbers, as they obviously share 2 as a prime factor with the range start and the range end, as well as multiples of 3 or 5 as they thus share factors with the range end. But, on the hope that it turns out to be at least a little bit instructive, the factorizations of all the numbers in our chosen range is given.

47563752567 $3 \times 3719 \times 4263131$
47563752568 $2^3 \times 71 \times 199 \times 420799$
47563752569 $31 \times 163 \times 9412973$
47563752570 $2 \times 3 \times 5 \times 1585458419$
47563752571 $29 \times 12941 \times 126739$
47563752572 $2^2 \times 7^2 \times 242672207$
47563752573 $3^2 \times 4657 \times 1134821$
47563752574 $2 \times 13 \times 823 \times 991 \times 2243$
47563752575 $5^2 \times 31769 \times 59887$
47563752576 $2^7 \times 3 \times 349 \times 354911$
47563752577 $11 \times 397 \times 593 \times 18367$
47563752578 $2 \times 173 \times 137467493$
47563752579 $3 \times 7 \times 3257 \times 695407$
47563752580 $2^2 \times 5 \times 83 \times 617 \times 46439$
47563752581 $19 \times 2503355399$
47563752582 $2 \times 3^4 \times 53 \times 59 \times 93893$
47563752583 $17 \times 43 \times 5171 \times 12583$
47563752584 $2^3 \times 149 \times 39902477$
47563752585 $3 \times 5 \times 67 \times 47327117$
47563752586 $2 \times 7 \times 3397410899$
47563752587 $13^2 \times 281442323$
47563752588 $2^2 \times 3 \times 11 \times 4513 \times 79843$
47563752589 $23 \times 61 \times 151 \times 224513$
47563752590 $2 \times 5 \times 4756375259$
47563752591 $3^2 \times 5284861399$
47563752592 $2^4 \times 47 \times 63249671$
47563752593 $7 \times 6794821799$
47563752594 $2 \times 3 \times 7927292099$
47563752595 $5 \times 32503 \times 292673$
47563752596 $2^2 \times 11890938149$
47563752597 $3 \times 15854584199$
47563752598 $2 \times 23781876299$
47563752599 $11 \times 37 \times 127 \times 373 \times 2467$




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Cross-references: prime factor, even numbers, trial division, JavaScript, calculator, size, squarefree, matching, factor, numbers, integers, consecutive, range

This is version 2 of examples of ranges of consecutive integers for Erdős-Woods numbers, born on 2007-11-25, modified 2007-11-28.
Object id is 10059, canonical name is ExamplesRangesOfConsecutiveIntegersForErdHosWoodsNumbers.
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Classification:
AMS MSC11A05 (Number theory :: Elementary number theory :: Multiplicative structure; Euclidean algorithm; greatest common divisors)

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