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Help! A remainder is chasing me ... #2


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#1 brhan

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Posted 06 October 2007 - 05:53 PM

The following puzzle is a variation of the question posted by bonanova.

I just found a number with an interesting property:

When I divide it by 2, the remainder is 1.
When I divide it by 3, the remainder is 1.
When I divide it by 4, the remainder is 1.
When I divide it by 5, the remainder is 1.
When I divide it by 6, the remainder is 1.
When I divide it by 7, the remainder is 1.
When I divide it by 8, the remainder is 1.
When I divide it by 9, the remainder is 1.
When I divide it by 10, the remainder is 1.

But when I divide it by 11, the remainder is 0.

Can you find it?
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#2 unreality

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Posted 06 October 2007 - 06:34 PM

Well obviously its a multiple of 11 and the number 1 beneath it is divisible by a bunch of numbers
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#3 Writersblock

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Posted 06 October 2007 - 10:12 PM

I had to big time brute this one, but I got a few that work. <!-- s:mrgreen: --><!-- s:mrgreen: -->

Smallest.
25201
11*2291
10*2520+1
9*2800+1
8*3150+1
7*3600+1
6*4200+1
5,4,3 are just 10,8,6 *2
2 just has to be an odd number

Others
52921
80641
108361
136081
163801
191521
219241

I am guessing this is an infinite set

Edited to add a couple more numbers
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#4 unreality

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Posted 07 October 2007 - 04:27 AM

I could write a computer program but it looks like ^ has already solved it
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