Can You Solve the Mystery of the Tape Recorder Riddle?

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The discussion revolves around a riddle contest where participants post logic problems and riddles, taking turns to answer and create new ones. The initial riddle involves a murder disguised as a suicide, which participants quickly solve by noting that the tape recorder could not have been rewound if the victim had indeed committed suicide. Various other riddles follow, including brain teasers about a man using stairs instead of an elevator, twins with confusing birth certificates, and a sequence puzzle. Participants engage in lively exchanges, sharing answers and explanations while also debating the format of the thread, with some suggesting that individual riddles should have separate threads for better organization. The conversation highlights the enjoyment of logic puzzles and the social interaction they foster, despite some concerns about the structure of the thread.
  • #61
does it involve adding, subtraction, mult... you get it, so does it?
 
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  • #62
It involves subtraction, but not in the way you think. It also involves addition, but in an even weirder way than the subtraction.

(Basically, if you think the pattern is anything akin to add one, subtract two, etc. you're on the wrong track. There is no such rule, really.)
 
  • #63
I have the feeling this puzzle is a bit too freakishly difficult, so here comes a big hint:

The sequence is very closely related to this one:

1
10, 1
11, 10, 2, 1
100, 11, 10, 3, 2, 1
...
?

If you're still stuck, I'll give the fifth row of the above sequence, although it kind of gives it away.
 
  • #64
30, 31, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1
 
  • #65
You have part of it, but you're missing the first 12 numbers, and one of the 32s.
 
  • #66
18, 19, 20, 21, 22, 23, 24, 25,, 26, 27, 28, 29, 30, 31, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1
 
  • #67
You have it right from 24 on, but the bit before that is wrong.
Think about how the first sequence might relate to the second sequence, and see if that helps. Tell me if you want the next row for the second sequence.
 
  • #68
20, 21, 22, 23, 24, 25, 24, 25,, 26, 27, 28, 29, 30, 31, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1
 
  • #69
Nope, colder.
 
  • #70
I give up, give another.
 
  • #71
Here's the original sequence:

1
2, 1
3, 3, 2, 1
4, 4, 4, 3, 2, 1
5, 9, 10, 11, 12, 12, 12, 12, 12, 12, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1

Here's the second sequence:

1
10, 1
11, 10, 2, 1
100, 11, 10, 3, 2, 1
101, 100, 22, 21, 20, 15, 14, 13 , 12, 11, 10, B, A, 9, 8, 7, 6, 5, 4, 3, 2, 1

Two entries in the last row should be a big hint as to what kind of problem this is. How do these sequences relate? Dividing into columns may help.
 
  • #72
To get the original sequence from the second sequence: find the representation in base 10 for each number in a row assuming that the number in the nth column is represented in base (n + 1). For instance, in the last row 101 base 2 is 5 base 10, 100 base 3 is 9 base 10, 22 base 4 is 10 base 10, 21 base 5 is 11 base 10, etc.
But I don't yet see how to get the second sequence.
 
  • #73
Now I see how to get the second sequence.

101 -1 (base 2) = 100
100 -1 (base 3) = 22
22 - 1 (base 4) = 21
21 - 1 (base 5) = 20
20 - 1 (base 6) = 15
etc.
So the next line in the second sequence is:
110, 101, 100, 33, 32, 31, 30, 27, 26, 25, 24, 23, 22, 21, 20, 1F, 1E, 1D, 1C, 1B, 1A, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, V, U, T, S, R, Q, P, O, N, M, L, K, J, I, H, G, F, E, D, C, B, A, 9, 8, 7, 6, 5, 4, 3, 2, 1

Converting to the original sequence we get:

6, 10, 16, 18, 20, 22, 24, 25, 26, 27, 28, 29, 30, 30, 31, 32, ..., 32, 31, 30, ..., 1
 
Last edited:
  • #74
Jimmy is correct. Good Job! You get the next puzzle.
 
  • #75
whew! :biggrin:
 
  • #76
j-j-j-j-jimmay!
 
  • #77
It is now my turn to propose a puzzle. I do not intend to do so. I mean no disrespect, but I sincerely hope that this thread will not continue. The reason is that when there is one puzzle per thread, we can more easily reference the puzzles. I'm sorry if I offend, and I open the floor to anyone who has a puzzle to propose and doesn't want it to show up in the forum in a thread of its own.
 
  • #78
The point of this forum is mostly to share interesting puzzles and to challenge each other to figure them out, not to catalogue brain teasers. If it were, it'd have more than 2 pages and my binary sequence thread will still be on here. This thread in particular, was created purely to have some fun, and to add some incentive to solving puzzles. I, for one, hope this thread lasts a while. (By the way, there are similar threads in General Physics and General Math)

Anyone's turn for a puzzle. I had the last one, I'm not taking it.
 
  • #79
Curved when I'm small
Flat when I'm all
Infanite is all
big, wide and tall

I extend in three directions
a paridox of perplexions

What am I?
 
  • #80
Space?...
 
  • #81
no, it's a lot harder.
 
  • #82
Earth?...
 
  • #83
warmer, still pretty far off
 
  • #84
It's a sphere[/color]
 
  • #85
jimmy got it, but he's not really doing this so people keep guessing
 
  • #86
a box might fit ?
 
  • #87
sorry...boxes[/color] aren't curved
 
  • #88
There is already a thread for this type of thing (one of the stickies, in fact) and it was abandoned. When each puzzle has a link of its own you can reference them better. Not store them, reference them. You can go straight to the puzzle you want when it has its own link.
 
  • #89
BicycleTree said:
There is already a thread for this type of thing (one of the stickies, in fact) and it was abandoned. When each puzzle has a link of its own you can reference them better. Not store them, reference them. You can go straight to the puzzle you want when it has its own link.
I like this thread. It's GREAT. You get new riddles quicker than you would if it wasn't here. Big deal if you can't reference them, you get lots and it's fun. Anyway, someone already brought this point up, you don't have to make it again. I can't answer this riddle though cos I already looked at the answer. I find it really hard not to look at the things in white. :mad:
 
  • #90
yomamma said:
Curved when I'm small
Flat when I'm all
Infanite is all
big, wide and tall

I extend in three directions
a paridox of perplexions

What am I?

Um... a closed 4-sphere? So it extends in 3 dimensions but still "curves" in 4-space, and "infinite" in 3-space.
 

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