Repunit

Bol

Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. In recreational mathematics, a repunit is a number like 11, 111, or 1111 that contains only the digit 1. The term stands for repeated unit and was coined in 1966 by Albert H. Beiler. A repunit prime is a repunit that is also a prime number. Any repunit in any base having a composite number of digits is necessarily composite. Only repunits (in any base) having a prime number of digits might be prime (necessary but not sufficient condition.)

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Pagina's: 88, Paperback, Betascript Publishers