[3] viXra:2305.0126 [pdf] replaced on 2025-02-17 09:22:42
Authors: Henri Caillaud
Comments: 23 Pages.
HAKEN and APPEL showed in their famous demonstration that the configuration consisting of two neighboring countries each having five neighbors was inevitable and irreducible. The present demonstration proposes a reduction of this configuration.
Category: Combinatorics and Graph Theory
[2] viXra:2305.0040 [pdf] submitted on 2023-05-06 01:46:21
Authors: Chongxi Yu
Comments: 3 Pages.
The four-color conjecture ( Guthrie's problem after F. Guthrie) is divided into 5 simple groups, every region is shared a common boundary with 1, 2, 3, 4, and unlimited regions sharing a common boundary (other than a single point) do not share the same color to make the problem much simpler and clearer, The four-color theorem is solved perfectly by using these simpler models.
Category: Combinatorics and Graph Theory
[1] viXra:2305.0003 [pdf] submitted on 2023-05-02 00:54:47
Authors: Atsu Dekpe
Comments: 3 Pages.
In this note, we give an alternate proof of the multinomial theorem following the number $ A_n^p $ using probabilistic approach. Although the multinomial theorem following the number $ A_n^p$ is basically a combinatorial result, our proof may be simple for a student familiar with only basic probability concepts.
Category: Combinatorics and Graph Theory