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). Many mathematicians believe it is the last even number to have this exact property before higher numbers begin having three or more pairs. Because of its factorization (

On an infinite chessboard, there are 68 distinct squares that are exactly three knight's moves away from any starting square. 68 is a "happy number," meaning that if

68 is a "happy number," meaning that if you take the sum of the squares of its digits and continue the process, you eventually reach 1. The Last Two-Digit "First" Number: In the digits of 68 in Culture and Daily Life

While 69 often gets the attention, mathematicians and number theorists find 68 far more compelling for several reasons. 68 is a "happy number

), a regular 68-sided polygon is considered constructible using only a compass and straightedge. 68 in Culture and Daily Life