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**dee93****Member**- Registered: 2013-08-12
- Posts: 19

Would I be right in saying that the first and second graphs are Hamiltonian and the third is Eulerian,unsure about the 4th?

*Last edited by dee93 (2013-08-15 00:31:10)*

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fourth is eulerian too

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'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

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**dee93****Member**- Registered: 2013-08-12
- Posts: 19

Agnishom wrote:

fourth is eulerian too

thanks so i am correct with the others?

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 6,116

I'm looking now. First is H but not E

More ....

Bob

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 6,116

Note: It is possible to be both eg. Four vertices connected as a square.

Second is not H and is E

Don't see how this is H? The middle vertex must be visited twice and three times if it is the start/finish.

Third is H but not E

Fourth is not H and is E

Bob

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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