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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

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18 answers to this question

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  colorclown26 said:
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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  Romulus064 said:
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?

:mellow:

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  Romulus064 said:
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

  Reveal hidden contents
  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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  Reveal hidden contents

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

i had to try as you tried

  Reveal hidden contents

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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  sachins19 said:
  Reveal hidden contents
0,1,4,13,23,48,69,118,154,235,290,411
i had to try as you tried
  Reveal hidden contents
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?

  Reveal hidden contents

In 4, the even triangular numbers are used.

In 1, the odd triangular numbers are used.

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  Pickett said:
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.

  Reveal hidden contents

Notice anything about the digits?

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  Reveal hidden contents

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

  Reveal hidden contents

Add 3 numbers

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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  sachins19 said:
  Reveal hidden contents
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
  Reveal hidden contents
Add 3 numbers

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. :o

Clapping.

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

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  sachins19 said:

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

  Reveal hidden contents

Add 3 numbers

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

  Reveal hidden contents
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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I have an alternative and simpler solution for #2

  Reveal hidden contents

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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  nobody said:
I have an alternative and simpler solution for #2
  Reveal hidden contents
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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