Watkins snark
Introduction In the mathematical field of graph theory, the '''Watkins snark''' is a snark with 50 vertices and 75 edges. It was discovered by John J. Watkins in 1989.As a snark, the Watkins graph is a connected, bridgeless cubic graph with chromatic index equal to 4.The Watkins snark is also non-planar and non-hamiltonian. It has book thickness 3 and queue number 2.Another well known snark on 50 vertices is the Szekeres snark, the fifth known snark, discovered by George Szekeres in 1973.
Gallery Image:Watkins snark 3COL.svg|The chromatic number of the Watkins snark is 3.Image:Watkins snark 4edge color.svg|The chromatic index of the Watkins snark is 4.
Edges 1,2, 1,4, 1,15, 2,3, 2,8, 3,6, 3,37, 4,6, 4,7, 5,10, 5,11, 5,22, 6,9, 7,8, 7,12, 8,9, 9,14, 10,13, 10,17, 11,16, 11,18, 12,14, 12,33, 13,15, 13,16, 14,20, 15,21, 16,19, 17,18, 17,19, 18,30, 19,21, 20,24, 20,26, 21,50, 22,23, 22,27, 23,24, 23,25, 24,29, 25,26, 25,28, 26,31, 27,28, 27,48, 28,29, 29,31, 30,32, 30,36, 31,36, 32,34, 32,35, 33,34, 33,40, 34,41, 35,38, 35,40, 36,38, 37,39, 37,42, 38,41, 39,44, 39,46, 40,46, 41,46, 42,43, 42,45, 43,44, 43,49, 44,47, 45,47, 45,48, 47,50, 48,49, 49,50
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