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#1 2010-12-19 00:21:14

Mariner
Member
Registered: 2010-06-16
Posts: 35

Sequencing

Hi, I was wondering if I could get your help on some particular number sequence questions and the tricks behind them.

Here are a few.

10, ?, 41, 17, 52, 09
15, ?, 70, 18, 52, 00

Thanks,

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#2 2010-12-20 00:00:57

bob bundy
Administrator
Registered: 2010-06-20
Posts: 8,151

Re: Sequencing

Hi Mariner,

I looked at these yesterday and hoped someone else would pick up your problem.  But alas, no one has.

The trouble is: there's no obvious pattern so no wonder you are stuck.  If you write down any five numbers at random, it is possible to fit a formula to them but that's not what you want I suspect.

These go up and down so that counts out 'plus x', 'subtract x' , 'multiply by x' and 'divide by x'.  So I thought maybe there are two interlocked sequences, but I haven't got enough numbers for that, so I have to admit defeat at the moment.  Sorry

But this post will  refresh the thread with New Post so maybe someone else will spot something.

Bob

Last edited by bob bundy (2010-12-20 00:01:22)


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#3 2010-12-21 07:40:50

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: Sequencing

Why are the last numbers written 09 and 00 rather than 9 and 0? Is that supposed to be a clue? roll

Last edited by JaneFairfax (2010-12-21 07:42:03)

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#4 2010-12-21 13:41:00

stapel
Member
Registered: 2006-07-22
Posts: 15

Re: Sequencing

Mariner wrote:

Hi, I was wondering if I could get your help on some particular number sequence questions and the tricks behind them.

Here are a few.

10, ?, 41, 17, 52, 09
15, ?, 70, 18, 52, 00

Try breaking up the numbers into sets of three digits. Remove the commas and try to find a pattern in:

. . . . .10_, _41, 175, 209

. . . . .15_, _70, 185, 200

There is no real "trick" to this. I just happened to think of it and it just happened to work.

cool

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#5 2010-12-22 11:49:05

soroban
Member
Registered: 2007-03-09
Posts: 452

Re: Sequencing

.




. .




.

Last edited by soroban (2010-12-22 11:51:16)

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#6 2017-11-07 18:51:39

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 886

Re: Sequencing

soroban wrote:


.

Because it contains "math"?

I knew it.

Last edited by Monox D. I-Fly (2017-11-07 18:52:04)

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