Discussion @ 1209. 1, 10, 100, 1000... @ Timus Online Judge

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Discussion of Problem 1209. 1, 10, 100, 1000...

Tips

Posted by Ruhul Amin 4 Feb 2021 05:02

The triangular sequence is behind the scene.
n belongs to triangular sequence if and only if (8n+1) is a square.