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 ## Encrypted message
 CFcSBwgCCBoHRhkKU1cGAA4AGU5YQR5THBwNFwoGGAxTQQMQVBUSBg4EAAwQRhUQVBUHFAQTGRpT QQMQVBkPERkECQAWDVwXX1BGEwgJBAwCBFRVHQRGUlFBShwaDVZTGBUFVUdBShsVA1tZBwNGUlFB ShoVB1wXX1BGFAQOSklOQR5HGh5AVRY=
+
+## Others
+### dodge-the-laser
+* Reference
+  * [Beatty sequence](https://en.wikipedia.org/wiki/Beatty_sequence)
+  * How to find A001951 A Beatty sequence: a(n)=floor(n\*sqrt(2)), stackexchange, https://math.stackexchange.com/questions/2052179/how-to-find-sum-i-1n-left-lfloor-i-sqrt2-right-rfloor-a001951-a-beatty-s