给一个长度为n nn的序列A0,A1,A2,...,An1 A_0,A_1,A_2,...,A_{n-1}A0,A1,A2,...,An1, 求∑i=0n2∑j=i+1n1lcmmod998244353sum_{i=0}^{n-2}sum_{j=i+1}^{n-1}lcm mod 998244353∑i=0n2∑j=i+1n1lcmmod998244353
给一个长度为 n n n的序列 A0,A1,A2,...,An−1 A_0,A_1,A_2,...,A_{n-1} A0,A1,A2,...,An−1。 求∑i=0n−2∑j=i+1n−1lcm(Ai,Aj) mod 998244353sum_{i=0}^{n-2}sum_{j=i+1}^{n-1}lcm(A_i,A_j) mod 998244353∑i=0n−2∑j=i+1n−1lcm(Ai,Aj) mod 998244353
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