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Number Sequences


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26 replies to this topic

#21 mudkip201

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Posted 03 February 2008 - 02:19 AM

i think ur doing a version of the Fibonacci number which is 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55
it is x + # before it
so 0+1=1 1+1=2 2+1=3 ...


try 0/1 1/1 2/1 3/2 5/3 8/5 13/8 21/13 34/21 55/34 89/55 ......
What number do the quotients swing around?
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#22 trojan2k8

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Posted 21 March 2008 - 04:39 PM

2. 1,4,9,18,35,68

2x+2,1,0
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#23 geronimo_b

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Posted 07 April 2008 - 07:06 PM

1, 4, 9, 18, 35, ?64

1+3=4

4+5=9
7
9+9=18
11
13
15

18+17=35
19
21
23
25
27

35+29=64
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#24 geronimo_b

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Posted 07 April 2008 - 09:26 PM

126, 63, 190, 95, 286, 143, 430, 215, 646, 323, 970, ?479

126+63+1=190
------------------286-190=96
--------------------------------144-96=48
--------------------------------------------72-48=24
190+95+1=286
------------------430-286=144
---------------------------------216-144=72
-----------------------------------------------108-72=36
286+143+1=430
------------------646-430=216
---------------------------------324-216=108
------------------------------------------------156-108=48
430+215+1=646
------------------970-646=324
---------------------------------480-324=156
646+323+1=970
------------------1450-970=480
970+479+1=1450
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#25 geronimo_b

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Posted 07 April 2008 - 09:38 PM

1, 2, 3, 6, 11, 20, 37, ?46
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#26 guru_bhai

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Posted 13 April 2009 - 09:37 AM

* 8723, 3872, 2387, ?

= 7238 {Cyclic permutation of numbers}

* 1, 4, 9, 18, 35, ?

=68

Difference of successive terms

3,5,9,17

Difference of successive terms

2,4,8,....

* 23, 45, 89, 177, ?

= 355

compare the series with

22,44,88,176,..


* 7, 5, 8, 4, 9, 3, ?

=10,2

formed by two series....

7,8,9,....
5,4,3,....


* 11, 19, 14, 22, 17, 25, ?

= 20,28,...

Formed by two series

11,14,17,.....
19,22,25,.....


* 3, 8, 15, 24, 35, ?

=48

Difference of successive terms

5,7,9,11,...


* 2, 4, 5, 10, 12, 24, 27, ?

=54,58

Multiply first term by 2 , ad 1 to get next term,
multiply by 2 add 2,
multiply by 2 add 3,...........


* 1, 3, 4, 7, 11, 18, ?

=29

add previous two terms to get next term....


* 99, 92, 86, 81, 77, ?

74

difference of successive terms

7,6,5,4,3,.....


* 0, 4, 2, 6, 4, 8, ?

=6,10

Formed by two series

0,2,4,....
4,6,8,.....


* 1, 2, 2, 4, 8, 11, 33, ?

= 37,148

add 1, multiply by 1
add 2 multiply by 2,
add 3 multiply by 3.....



* 1, 2, 6, 24, 120, ?

=720

factorials.


* 1, 2, 3, 6, 11, 20, 37, ?

=68

successive difference of terms

1,2,3,5,9,17

successive difference of terms

1,1,2,4,8,.....


* 5, 7, 12, 19, 31, 50, ?

=81,...

add previous two terms to get next term....


* 27, 82, 41, 124, 62, 31, 94, 47, 142, 71, 214, 107, ?

= 322,161

Alternatively multiply by 3, add+1 and divide by 2

27*3 +1=82
82/2 = 41
41*3 +1=124
124/2 =62
....


* 126, 63, 190, 95, 286, 143, 430, 215, 646, 323, 970, ?

=485,1456

Alternatively divide by 2 and multiply by 3, +1

126/2 =63
63*3+1=190
190/2 =95
95*3+1=286


* 4, 7, 15, 29, 59, 117, ?

=235,469

Multiply by 2 add and subtract 1 alternatively.

4*2 -1 =7
7*2+1=15
15*2-1=29
29*2+1=59



* 2, 3, 2, 3, 2, 4, 2, 3, 2, 3, 2, 5, 2, 3, 2, 3, 2, 4, 2, 3, 2, 3, 2, 5, 2, 3, 2, 3, 2, 4, 2, 3, 2, 3, 2, 5, ?

If we remove all the alternate 2 we get

3,3,4,3,3,5,3,3,4,3,3,5,3,3,4,3,3,5,

ie a repeating sequence of 3,3,4,3,3,5.

Ans = 2,3,2,3,2,4,2,3,2,3,2,5


* 4, 4, 341, 6, 4, 4, 6, 6, 4, 4, 6, 10, 4, 4, 14, 6, 4, 4, 6, 6, 4, 4, 6, 22, 4, 4, 9, 6, ?

Clearly if we remove double sequences of 4 we get

341 ,6 ,6 ,6 ,6 ,10, 14, 6, 6 ,6 ,6 , 22 , 9 , 6

If we remove sequences of 4 6's we get

341,10,14,22,9,

which do not forms any sequence so,,,,,this question seems to be wrong......
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#27 matthew laming

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Posted 18 October 2010 - 10:23 PM

Heres one you wont get ;)

http://brainden.com/...-number-puzzle/

if you like sequences try this one. the mother of all sequences. mwhahahaha
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