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## Question

1 2 4 6 16 18 __

What's next?

The first person please post the answer. Then someone else give the sequence. Thank you.

It is less than 100.

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64?

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64?

It is. Now can someone get the sequence?

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How about the term after that?

Could be 54.

Could be 66.

1 2 4 6 16 18 64 54 256 162 ...

Here you start with 1 2, then multiply alternate numbers by 2 then 3 to get the term after next:

1x4=4

2x3=6

4x4=16

6x3=18

16x4=64 ... agreeing with 64 but then

18x3=54

64x4=256

54x3=162 and so on; this sequence does not increase with each term

1 2 4 6 16 18 64 66 100 ...

Here you increase the number over the previous term

until the number of factors increases by one.

1: 1 - [1 factor]

2: 1 2 - [2 factors]

4: 1 2 4 - [3 factors]

6: 1 2 3 6 - [4 factors]

16: 1 2 4 8 16 - [5 factors]

18: 1 2 3 6 9 18 - [6 factors]

64: 1 2 4 8 16 32 64 - [7 factors]

66: 1 2 3 6 11 22 33 66 - [8 factors]

100: 1 2 4 5 10 20 25 50 100 - [9 factors] and so on; this sequence continues to increase.

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1 2 4 6 16 18 __

What's next?

The first person please post the answer. Then someone else give the sequence. Thank you.

It is less than 100.

2^0, 2^0+2, 2^2, 2^2+2, 2^4,2^4+2, 2^6,2^6+2,

raising to even powers of 2, then add 2, then next even power of 2, then add 2

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bonanova your second guess is correct. That alternating by x3 x4 thing is just a coincidence.

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Odd terms are powers of 4; Even terms are twice the powers of 3 (Powers start at 0)

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