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#1 2009-06-08 21:37:40
- wintersolstice
- Real Member
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seven and thirteen
7 and 13 are the first two happy primes and 91 (7×13) is also a happy number. this means that 19 is happy, this is the 3rd happy prime!
Why did the chicken cross the Mobius Band?
To get to the other ...um...!!!
#2 2009-06-08 22:00:11
- ganesh
- Moderator
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Re: seven and thirteen
What are happy primes?
Character is who you are when no one is looking.
#3 2009-06-08 22:33:47
- mathsyperson
- Moderator
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Re: seven and thirteen
Happy numbers are related to a sequence where each term is determined by the sum of the squares of the previous term's digits. eg.
7
49 (= 7²)
97 (= 4² + 9²)
130
10
1
1
1
...
A happy number is a number that initiates a sequence that goes to 1, like 7 does above.
An unhappy number will instead eventually fall into the following loop:
4, 16, 37, 58, 89, 145, 42, 20, 4...
Why did the vector cross the road?
It wanted to be normal.
#4 2009-06-10 16:36:13
- DarkLightA
- Member
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Re: seven and thirteen
Hmm.. Never heard of this.. Is there a use for this sequence?
#5 2009-06-14 00:59:52
- RickIsAnIdiot
- Novice
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Re: seven and thirteen
Happy numbers are related to a sequence where each term is determined by the sum of the squares of the previous term's digits. eg.
7
49 (= 7²)
97 (= 4² + 9²)
130
10
1
1
1
...
For mathsyperson
Quote:
A happy number is a number that initiates a sequence that goes to 1, like 7 does above.
An unhappy number will instead eventually fall into the following loop:
4, 16, 37, 58, 89, 145, 42, 20, 4...
RickIsAnIdiot
Do you have any more Happy Number examples.
#6 2009-06-14 01:07:17
- bobbym
- Administrator
Online
Re: seven and thirteen
Hi Rick;
http://en.wikipedia.org/wiki/Happy_number
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#7 2009-06-14 22:37:05
- RickIsAnIdiot
- Novice
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Re: seven and thirteen
For bobbym
Quote:
http://en.wikipedia.org/wiki/Happy_number
RickIsAnIdiot
Thanks bobbym! keep up the good work..
#8 2009-06-14 23:23:58
- bobbym
- Administrator
Online
Re: seven and thirteen
Hi Rick;
Please don't be offended but I don't feel comfortable calling anyone an idiot so may I call you Rick. Anyway welcome to the forum.
Last edited by bobbym (2009-06-14 23:43:15)
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#9 2009-06-16 22:11:58
- RickyIsAnIdiot
- Banned
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Re: seven and thirteen
For bobbym
Quote:
Hi Rick;
Please don't be offended but I don't feel comfortable calling anyone an idiot so may I call you Rick. Anyway welcome to the forum.
RickyIsAnIdiot
That's OK! you can call me Rick,#ick,#rick it's only names? Knowing the meaning's is the main thing...
Last edited by RickyIsAnIdiot (2009-06-16 22:13:47)
#10 2009-06-17 01:09:06
- bobbym
- Administrator
Online
Re: seven and thirteen
That's OK! you can call me Rick,#ick,#rick it's only names? Knowing the meaning's is the main thing...
I don't appreciate what you are trying to do here. The meaning... what are you implying?
Last edited by bobbym (2009-06-17 03:11:49)
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#11 2009-06-17 22:22:18
- Kurre
- Power Member
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Re: seven and thirteen
There are two different accounts posting here, both RICKisanidiot and RICKYisanidiot, imo a clear violence to the multiple account rule (which I think exist on this forum?)