有向图n·_5(n≡0(mod2)的优美性

On the proof of the directed graph n·_5(n≡0(mod2)) is a graceful graph

利用构造性方法 ,证明了 :(1)n·C→5是优美图的充要条件是n≡ 0 (mod 2 ) ;(2 )当n≡ 0 (mod 2 ) ,1≤i≤k时 ,优美图n·C→5中C→5(i) 的弧优美值之和为 2 (q + 1) ,当k+ 1≤i≤ 2k时 ,C→5的弧优美值之和为 3 (q + 1) .

Using the structure method,we show that(1)n·C→ 5 is a graceful graph if and only if n≡0(mod2);(2) in graceful graph n·C→ 5,the sum of arc graceful value of C→ 5 (i) is 2(q+1) when n≡0(mod2) and 1≤i≤k;under condition k+1≤i≤2k,the sum of arc graceful value of C→ 5 (i) is 3(q+1).