(2005·南宁)如图是与杨辉三角有类似性质的-三角形数垒,a、b、c、d是相邻两行的前四个数(如图所示),那么当a=8时,c=
(2005·淮安)已知一列数:1,-2,3,-4,5,-6,7,…将这列数排成下列形式:按照上述规律排下去,那么第10行从左边数第5个数等于| 1 |
| 3 |
| 1 |
| 5 |
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 5 |
| 1 |
| 5 |
| 1 |
| 7 |
| 1 |
| 2 |
| 1 |
| 5 |
| 1 |
| 7 |
| 1 |
| 7 |
| 1 |
| 9 |
| 1 |
| 2 |
| 1 |
| 7 |
| 1 |
| 9 |
| 1 |
| 2 |
| 1 |
| 4 |
| 1 |
| 4 |
| 1 |
| 6 |
| 1 |
| 6 |
| 1 |
| 8 |
| 1 |
| 18 |
| 1 |
| 20 |
| 9 |
| 40 |
| 9 |
| 40 |
| 剪裁次序 | 1 | 2 | 3 | … | 10 |
| 所得扇形总个数 | 4 | 7 | … |