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AIME 2026 II · 第 1 题

AIME 2026 II — Problem 1

专题
Contest Math
难度
L4
来源
AIME

题目详情

Problem

Find the sum of the 1010th terms of all arithmetic sequences of integers that have first term equal to 44 and include both 2424 and 3434 as terms.

解析

Solution 1

Suppose we have an arithmetic sequence of integers that includes 4,24,4, 24, and 3434. The common difference of the sequence dd, must satisfy

d244 and d344    dgcd(244,344)=10d\mid 24-4 \text{ and } d \mid 34-4 \implies d \mid \text{gcd}(24-4, 34-4) = 10 Since dd must be positive, d=1,2,5,10d=1, 2, 5, 10. The 10th terms of each of these sequences is 13,22,49,9413,22,49,94, respectively, so the sum is 178\boxed{178}. ~sillybone