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#1 2007-08-13 18:31:21

clemseed
Member
Registered: 2007-08-13
Posts: 1

Number pattern problem

Hi!

Anyone able to find the pattern?

the last digit derived from the first 8 digits.
For example, 90267488    3

(9 x a + 0 x b + 2 x c + 6 x d + 7 x e + 4 x f + 8 x g + 8 x h) Mod i = 3
where a to i are integers.


90267488    3
90267489    7
90267490    6
90267491    0
90267492    3
90267493    7
90267494    5
90267495    4
90267496    8
90267497    1
90267498    5
90267499    9
90267500    5
90267501    9
90267502    2
90267503    6
90267504    0
90267505    3
90267506    7
90267507    5
90267508    4
90267509    8
90267510    7
90267511    5
90267512    4
90267513    8
90267514    1
90267515    5
90267516    9
90267517    2
90267518    6
90267519    0
90267520    9
90267521    2
90267522    6
90267523    0

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#2 2007-08-14 02:58:27

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

Re: Number pattern problem

Just look at the last
two digits, since the
other ones don't change.
00    5
        +4
01    9
        -7
02    2
        +4
03    6
        -6
04    0
        +3
05    3
        +4
06    7
        -2
07    5
        -1
08    4
        +4
09    8



10    7
        -2
11    5
        -1
12    4
        +4
13    8
        -7
14    1
        +4
15    5
        +4
16    9
        -7
17    2
        +4
18    6
        -6
19    0




20    9
        -7
21    2
        +4
22    6
        -6
23    0

Since the plus minus values are not constant,
your equation is not right I presume.
Try to find a more complicated equation.
Or use hash tables with double digits, etc...
Actually, maybe I'm wrong.
Use big prime numbers in the products, maybe the
mod function will create this randomness.
Not sure yet...

Last edited by John E. Franklin (2007-08-14 03:00:41)


igloo myrtilles fourmis

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#3 2007-08-14 03:16:17

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

Re: Number pattern problem

Hey I just noticed that
6037548 occurs twice in you list of numbers.
Did you see that?
Going down the check codes.


igloo myrtilles fourmis

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#4 2007-08-14 03:17:34

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

Re: Number pattern problem

Also 159 occurs twice!


igloo myrtilles fourmis

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#5 2007-08-14 03:19:41

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

Re: Number pattern problem

And 59260 occurs twice and
9260 occurs 3 times in your check codes going downward in the list.


igloo myrtilles fourmis

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