BrainDen.com - Brain Teasers
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## Question

These are harder the other ones on this sight.

But with the proper insight, they can be done.

1. 0,1,5,11,27,42,78,106...

2. 2,2,4,10,14,24,42...

3. 3,4,6,8,12,14,18,20,24,30...

4. 0,1,4,13,23,48,69,118

5. 0,2,7,15,26,40,57,77

6. 1,1,3,4,6,9,10,16

7. 1,1,2,3,7,16

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I doubt you will answer this for me but are these math riddles or more of like application sequences like

31,30,31,30=January, Feburary,March,April, etc.

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I doubt you will answer this for me but are these math riddles or more of like application sequences like

31,30,31,30=January, Feburary,March,April, etc.

They're mathematical sequences like:

1,2,3,4,5,6,7,8,9 (0+1)(1+1)(2+1)...

1,4,9,16,25,36,49,64 (1^2)(2^2)...

except they're not as easy

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They're mathematical sequences like:

1,2,3,4,5,6,7,8,9 (0+1)(1+1)(2+1)...

1,4,9,16,25,36,49,64 (1^2)(2^2)...

except they're not as easy

Oh, ok. (I probably don't belong here then. I don't take algebra until next year>)

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I sit here in the silence and wonder if there is anyone out there. Shall I go down into the midst of obscurity, or shall I choose the correct moment to post myself to the top of the forum? The real question is, Is their anyone around that likes math?

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i am bored of solving these kind of puzzles....need something new

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These are harder the other ones on this sight.

But with the proper insight, they can be done.

1. 0,1,5,11,27,42,78,106...

2. 2,2,4,10,14,24,42...

3. 3,4,6,8,12,14,18,20,24,30...

4. 0,1,4,13,23,48,69,118

5. 0,2,7,15,26,40,57,77

6. 1,1,3,4,6,9,10,16

7. 1,1,2,3,7,16

1. 0,1,5,11,27,42,78,106, 170, 215, 315, 381 ...
2. 2,2,4,10,14,24,42...
3. 3,4,6,8,12,14,18,20,24,30, 32, 38, 42, 44, 48, 54, 60 ...
4. 0,1,4,13,23,48,69,118
5. 0,2,7,15,26,40,57,77, 100, 126, 155, 187, 222, 260, 301 ...
6. 1,1,3,4,6,9,10,16, 15, 25, 21, 36, 28, 49, 36, 64 ...
7. 1,1,2,3,7,16, 65, 321, 4546, 107587 ...

Spoiler for what:

1. for odd n add triangular number = n(n+1)/2; for even n add square = n2
2. ...
3. primes + 1
4. ...
5. number of cards in an n-tiered house of cards = n(3n+1)/2
6. odd: triangular numbers; even: squares
7. a(n) = a(n-1) + a(n-2)2 = ?

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0,1,4,13,23,48,69,118,154,235,290,411

i had to try as you tried

Sequence 0,1,4,13,23,48,69,118,154,235,290,411

Differences 1 3 9 10 25 21 49 36 81 55 121

odd numbers are square of 1 3 5 7 9 11

and even numbers 3*1 5*2 7*3 9*4 11*5

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0,1,4,13,23,48,69,118,154,235,290,411
i had to try as you tried
Sequence 0,1,4,13,23,48,69,118,154,235,290,411

Differences 1 3 9 10 25 21 49 36 81 55 121

odd numbers are square of 1 3 5 7 9 11

and even numbers 3*1 5*2 7*3 9*4 11*5

Good one. Now what's #2?

In 4, the even triangular numbers are used.

In 1, the odd triangular numbers are used.

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Yeah, I see numbers 1, 3, 4 (thanks to sachins), 5, 6, and 7...but yeah, 2 is eluding me right now...hmm...

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Yeah, I see numbers 1, 3, 4 (thanks to sachins), 5, 6, and 7...but yeah, 2 is eluding me right now...hmm...

Yeah, I kind of realized it would be a hard one when I made it, but here's a small hint.

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66

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2,2,4,10,14,24,42,62,92,134

It might not be the answer yo are expecting but nevertheless it could be one of the answers

8,16,28,48,80,128,196,288

Diff of 1st 2 nos.

8,12,20,32,48,68,92

Diff of 1st 2 nos.

4,8,12,16,20,24

Edited by sachins19

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2,2,4,10,14,24,42,62,92,134
It might not be the answer yo are expecting but nevertheless it could be one of the answers

8,16,28,48,80,128,196,288

Diff of 1st 2 nos.

8,12,20,32,48,68,92

Diff of 1st 2 nos.

4,8,12,16,20,24

Wow.

Clapping.

I think he had something else in mind from his clue, but what you found is pretty solid.

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It might not be the answer yo are expecting but nevertheless it could be one of the answers

8,16,28,48,80,128,196,288

Diff of 1st 2 nos.

8,12,20,32,48,68,92

Diff of 1st 2 nos.

4,8,12,16,20,24

2,2,4,10,14,24,42,62,92,134

I congratulate you, it seems to be solved.

But I couldn't get it, it's my fault of course.

How did you add 3 numbers to 2,2,4,10... and get 8,16,28....

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How did you add 3 numbers to 2,2,4,10... and get 8,16,28....

Add 2, 2, 4 = 8 then 2, 4, 10 = 16

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I have an alternative and simpler solution for #2

It's a kind of fiobonucci? series beginning with 2,2 and in base 6.

2+2=4

4+2=6=10(base 6)

4+10=14(base 6)

10+14=24(base 6)

14+24=42(base 6)

then

24+42=110(base 6)

42+110=152(base 6)

110+152=302(base 6)

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good one...

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I have an alternative and simpler solution for #2
It's a kind of fiobonucci? series beginning with 2,2 and in base 6.

2+2=4

4+2=6=10(base 6)

4+10=14(base 6)

10+14=24(base 6)

14+24=42(base 6)

then

24+42=110(base 6)

42+110=152(base 6)

110+152=302(base 6)

Nobody got it

(I mean the Person)

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