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

You are not logged in.

- Topics: Active | Unanswered

**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)*

Offline

fourth is eulerian too

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

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

I'm not crazy, my mother had me tested.

Offline

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

Agnishom wrote:

fourth is eulerian too

thanks so i am correct with the others?

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,662

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

More ....

Bob

Children are not defined by school ...........The Fonz

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

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,662

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

Children are not defined by school ...........The Fonz

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

Offline