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The Boeing 727 became the first threeengine jet built for commercial service. 727 = 1! + (1 + 2)! + (1 + 2 + 3)!. [Van Doorn] The smallest odd prime that can be represented as the sum of a cube and its reversal (512 + 215). [Gupta] The first prime whose square (528529) can be represented as the concatenation of two consecutive numbers. [De Geest] Probably the only palindromic prime that can be expressed by the form n!+(n+1). [Silva] 727 starts the first chain of four palindromic primes, each formed from the previous one in forward and reverse order: 727, 72727, 727272727, 72727272727272727. [Silva] The sum of the first five threedigit primes with midlle digit zero. [Silva] The smallest primedigit prime that can be represented as the sum of a number and its reversal in three different ways (116+611, 215+512, 314+413). [Loungrides] (x) > li(x) somewhere near e^{727}. Between 2 and 313 and between 317 and 733 there are 65 primes, and (3132) + (733317) = 727. Between 2 and 317 and between 331 and 743 there are 66 primes; (3172) + (743331) = 727. Can there be more than two terms like 65 and 66 to find a prime? [Bergot]
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