Benedict Irwin edited The 90 Thing.tex  over 9 years ago

Commit id: 1dd246f4298ec9a53b9251245085dcbdf244c423

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So from the table above in the first $22$ concatenations, we can see $2,3,9,15,...$ are prime.  Of course in the spirit of OEIS: we have $A054416$ which will continues that sequence for a little longer as 2, 3, 9, 15, 26, 33, 146, 320, 1068, 1505...  However the algorithm above gives the following as prime candidates $0,1,2,3,5,6,8,9,11,14,15,18,20,21,23... $0,1,2,3,5,6,8,9,11,14,15,18,20,21,23...$  may be prime. Well, the real prime numbers are a subset of that which is good to start with. Checking also 26,33,146,320,1068 and 1505 from the OEIS:sequence are also thrown in as potential primes, by the algorithm which is another good sign. But there are many more which aren't prime. Why?