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## Question

What is the 100th number in this sequence?

1 3 7 12 18 26 35 45 56 69

?!??.!!!

## 21 answers to this question

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6314

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incorrect itachi-san.

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What is the 100th number in this sequence?

1 3 7 12 18 26 35 45 56 69

?!??.!!!

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

with every increment (n+1) is added, though this procedure skips every (insert formula here) number beginning with 3. In English it doesn't add 3,7,12,18,25,33,42,52,etc.. until you get to 102 which should be the 100th place.

Edited by itachi-san

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Hey my friend, LTNS.

This one's a challenge.

My first answer does not fit the clue so I'll keep at it:

. 83 98 114 131 150 170 191 213 236 260
. 286 313 341 370 400 431 463 497 532 568
. 605 643 682 722 763 806 850 895 941 988
. 1036 1085 1135 1186 1239 1293 1348 1404 1461 1519
. 1578 1638 1699 1761 1825 1890 1956 2023 2091 2160
. 2230 2301 2373 2446 2520 2596 2673 2751 2830 2910
. 2991 3073 3156 3240 3325 3411 3498 3587 3677 3768
. 3860 3953 4047 4142 4238 4335 4433 4532 4632 4733
. 4836 4940 5045 5151 5258 5366 5475 5585 5696 5808
`.	1	3	7   12   18   26   35   45   56   69 `

5808

My generating series was:

1 2 4 5 6 8 9 10 11 13 14 15 16 17 19 20 21 22 23 24 26 27 28 29 30 31 32 34 35 36 37 38 39 40 41 43 44 45 46 47 48 49 50 51 53 54 55 56 57 58 59 60 61 62 64 65 66 67 68 69 70 71 72 73 74 76 77 78 79 80 81 82 83 84 85 86 87 89 90 91 92 93 94 95 96 97 98 99 100 101 103 104 105 106 107 108 109 110 111 112

The red numbers are your deltas, the remaining ones I inferred.

The series that generated it was

1 2

1 1 2

1 1 1 2

1 1 1 1 2

1 1 1 1 1 2

1 1 1 1 1 1 2

1 1 1 1 1 1 1 2

1 1 1 1 1 1 1 1 2

1 1 1 1 1 1 1 1 1 2

1 1 1 1 1 1 1 1 1 1 2

1 1 1 1 1 1 1 1 1 1 1 2

1 1 1 1 1 1 1 1 1 1 1 1 2

1 1 1 1 1 1 1 1 1 1

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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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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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The 100th number is 5808.

Is it correct?

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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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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

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Stop groveling ...

I didn't mean anything negative by my comment,

only that we both have to think a little more about

this. Writersblock is pretty shrewd at times, he

may have us going for awhile.

And we apparently did note the same pattern.

I'm stumped for the moment ... hitting the sack.

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Stop groveling ...

I didn't mean anything negative by my comment,

only that we both have to think a little more about

this. Writersblock is pretty shrewd at times, he

may have us going for awhile.

And we apparently did note the same pattern.

I'm stumped for the moment ... hitting the sack.

Sorry , if you misunderstood my comment . And I did not see anything negative in your comment. It was all the way +(ve).

And agreed , I will stick with this puzzle until it is solved.

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I think like I have another pattern.

Sequence : 1 3 7 12 18 26 35 45 56 69

1+2=3.

Now 3 is result. According to me , 3 must be left out from the series addition. It is left out.

3+4=7.

Now 7 is a result and it is also left out from addition.

Likewise all the numbers coming as a result must be left out .

This one definitely looks bright.

Verify my answer Writersblock and bononova.

Edited by grey cells

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OK , is it 5764?

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Appears that you discard used numbers, that takes too much work to prove, and program

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What is the 100th number in this sequence?

1 3 7 12 18 26 35 45 56 69

?!??.!!!

Shouldn't be 25 instead of 26?

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Shouldn't be 25 instead of 26?

I think 26 is ok. 18+8=26. we don't have 18+7(=25) in the sequence because 7 already appeared there.

Edited by brhan

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What is the 100th number in this sequence?

1 3 7 12 18 26 35 45 56 69

?!??.!!!

Is it this number-5764

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5764

6066 .... ?=6 and !=0

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Great job on the sequnce guys. It is, indeed, 5764, by adding sequential numbers but skipping those that are self-referential.

Now, anyone break the code? The code reads 5764. Anyone see how?

Brhan, your code is incorrect, sorry.

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Maybe the code was too hard.

Here's the answer if you want it.

?=2, !=1, .=0

It's the same answer, but in base 3.

5764 = 21220111 = ?!??.!!!

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Maybe the code was too hard.

Here's the answer if you want it.

?=2, !=1, .=0

It's the same answer, but in base 3.

5764 = 21220111 = ?!??.!!!

That was way too hard(atleast for me) , but hats-off to your thinking.

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