Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

You are not logged in.

## #1 2006-02-18 12:14:53

anyarules
Member
Registered: 2005-07-24
Posts: 29

### number sequences

pls complete this::

* 81  27  135  45  __  75  __

* 4  10  18  28  40  __  __  __

* 11  20  27  __  35  36

thanx guys!!;):D:cool:

Offline

## #2 2006-02-18 12:37:21

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

### Re: number sequences

1.  /3, *5, /3, *5...
2. +6, +8, +10, +12, ....
3. +9, +7, +5, +3, +1

Last edited by Ricky (2006-02-18 12:38:35)

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

## #3 2006-02-19 18:26:10

anyarules
Member
Registered: 2005-07-24
Posts: 29

### Re: number sequences

thanx

but man!

Last edited by anyarules (2006-02-19 18:26:43)

Offline

## #4 2006-02-19 18:45:50

ganesh
Registered: 2005-06-28
Posts: 24,221

### Re: number sequences

anyarules, Ricky gave the clues. I shall give the answers.

* 81, 27, 135, 45, 225 , 75, 375

* 4, 10, 18, 28, 40, 54, 70, 88

* 11, 20, 27, 32, 35 , 36

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

## #5 2006-02-20 08:49:51

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

### Re: number sequences

anyarules, Ricky gave the clues. I shall give the answers.

I just did that because I know that ganesh is clueless.

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Offline

## #6 2006-05-30 03:11:07

sabdulsamee
Member
Registered: 2006-05-11
Posts: 9

### Re: number sequences

I have a sequence to share with everyone
Its name is Even Squares and it goes like this: 4, 16, 36, 64, 100, 144, 196, 256, 324, 400, 484, 576, 676, 784, 900, 1024, 1156, 1296, 1444, 1600, 1764, 1936, 2116, 2304, 2500, 2704, 2916, 3136, 3364, 3600, 3844, 4096, 4356, 4624, 4900, 5184, 5476, 5776, 6084, 6400, 6724, 7056, 7396, 7744, 8100, 8464, 8836, 9216, 9604, ...

Offline

## #7 2006-05-30 03:50:40

sabdulsamee
Member
Registered: 2006-05-11
Posts: 9

### Re: number sequences

sabdulsamee wrote:

I have a sequence to share with everyone
Its name is Even Squares and it goes like this: 4, 16, 36, 64, 100, 144, 196, 256, 324, 400, 484, 576, 676, 784, 900, 1024, 1156, 1296, 1444, 1600, 1764, 1936, 2116, 2304, 2500, 2704, 2916, 3136, 3364, 3600, 3844, 4096, 4356, 4624, 4900, 5184, 5476, 5776, 6084, 6400, 6724, 7056, 7396, 7744, 8100, 8464, 8836, 9216, 9604, ...

These are the first 49 terms of the sequence of which
the first term is 4,
the second term is 16, and
the third term is 36. Now
4 is   2 times  2, and   2 is  1 plus  1.
16 is   4 times  4, and   4 is  2 plus  2.
36 is   6 times  6, and   6 is  3 plus  3.
64 is   8 times  8, and   8 is  4 plus  4.
100 is 10 times 10, and 10 is  5 plus  5.
144 is 12 times 12, and 12 is  6 plus  6.
196 is 14 times 14, and 14 is  7 plus  7.

Offline

## #8 2006-05-30 04:18:41

ganesh
Registered: 2005-06-28
Posts: 24,221

### Re: number sequences

Hi sabdulsamee,
Welcome to the forum.
The nth term of the series you have given is (2n)²,
thus the first term would be (2 x 1)²=2² = 4
and the second would be (2 x 2)²=4² = 16, and so on.
The differences of the terms of this series would form an Arithmetic Progression.
The differences are 12, 20, 28, 36, 44, 52, .....
You can see that the common difference of the terms in the series is 8.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline