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21 replies to this topic

#1 Writersblock

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Posted 28 March 2008 - 04:43 AM

What is the 100th number in this sequence?

1 3 7 12 18 26 35 45 56 69

Here's the answer in code:

?!??.!!!

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#2 itachi-san

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Posted 28 March 2008 - 05:14 AM

Spoiler for my answer

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#3 Writersblock

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Posted 28 March 2008 - 05:22 AM

incorrect itachi-san.
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#4 itachi-san

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Posted 28 March 2008 - 05:35 AM

What is the 100th number in this sequence?

1 3 7 12 18 26 35 45 56 69

Here's the answer in code:

?!??.!!!


I always forget to carry the 1 or something stupid with my formulas

Spoiler for my reasoning

Edited by itachi-san, 28 March 2008 - 05:35 AM.

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#5 bonanova

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Posted 28 March 2008 - 05:59 AM

Hey my friend, LTNS.
This one's a challenge.

My first answer does not fit the clue so I'll keep at it:
Spoiler for FWIW, here's the sequence I constructed

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#6 Writersblock

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Posted 28 March 2008 - 05:59 AM

AS you increase in your "skipped" numbers, you are making a mistake itachi. I think you don't quite have the pattern yet...
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#7 Writersblock

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Posted 28 March 2008 - 06:01 AM

You are off too bona, but good try. Good to be back for the few hours I have tonight. :)

The "code" is really hard and a bonus. I'm thinking people will get the pattern WAY before cracking the code.
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#8 grey cells

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Posted 28 March 2008 - 06:46 AM

Spoiler for The hard way

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#9 bonanova

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Posted 28 March 2008 - 06:50 AM

grey cells, it wasn't correct when I posted it,
so I'm guessing it's not correct now either. ;)

But it's nice to know two great minds think alike ... !
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#10 grey cells

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Posted 28 March 2008 - 07:01 AM

grey cells, it wasn't correct when I posted it,
so I'm guessing it's not correct now either. ;)

But it's nice to know two great minds think alike ... !

Sorry , Bononova. Did not go through your spoiler. I did not want to get a hint and hence did not know it was the same.:)
But the series really works . I tried it out manually(ok.. using calculator ;) ) but still it took quite a while.
And coming to the second part , it would not be proportional if you compare you brain with mine. Because yours has loads of wisdom in it , while mine has just grains of it. ;)

Edited by grey cells, 28 March 2008 - 07:02 AM.

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