943. Self Describing Sequences

Given two unequal positive integers a and b, we define a self-describing sequence consisting of alternating runs of as and bs. The first element is a and the sequence of run lengths is the original sequence.

For a=2,b=3, the sequence is:

2,2,3,3,2,2,2,3,3,3,2,2,3,3,2,2,3,3,3,2,2,2,3,3,3,...

The sequence begins with two 2s and two 3s, then three 2s and three 3s, so the run lengths 2,2,3,3,... are given by the original sequence.

Let T(a,b,N) be the sum of the first N elements of the sequence. You are given T(2,3,10)=25, T(4,2,104)=30004, T(5,8,106)=6499871.

Find T(a,b,22332223332233) for 2a223, 2b223 and ab. Give your answer modulo 2233222333.

943. 自描述序列

给定两个不等的正整数 a,b,我们用这两个正整数,生成惟一一个满足如下要求的自描述序列 {cn}

例如 a=2,b=3 时,该序列形如:

2,2,3,3,2,2,2,3,3,3,2,2,3,3,2,2,3,3,3,2,2,2,3,3,3,...

T(a,b,N) 为:用 a,b 生成的自描述序列的前 N 个元素之和。已知 T(2,3,10)=25T(4,2,104)=30004T(5,8,106)=6499871

求所有满足 2a,b223abT(a,b,22332223332233) 之和,给出答案模 2233222333 的值。


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