观察下列三角形数表其中从第二行起每行的每一个数为其肩膀上两树之和则该表的最后一个数是?
问题描述：
观察下列三角形数表其中从第二行起每行的每一个数为其肩膀上两树之和则该表的最后一个数是?
1 2 3 4 5 6 7 8················ 97 98 99100
3 5 7·····························195 197 199
8 12 ······························392396
································
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· · · ··
·····
···
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求最后一个数
答
1=1
1,2=（1+2）*2^0
1,2,3=(1+3）*2^1
1,2,3,4=（1+4）*2^2
1,100=（1+100）*2^98
具体推导和杨辉三角有关系,有兴趣可以私下交流.