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Observing that 521, M(521), 953, 61, and M(61) are prime, it is curious that 521*2^953+61 is also prime. [Noll]
The first emirp p such that 2p+1 and 3p+2 are prime. [Loungrides] The largest threedigit centered heptagonal number. [Homewood] The smallest emirp p such that prime(p)*p + (p) yields another emirp. [Bajpai]
(There is one curio for this number that has not yet been approved by an editor.)
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