deletions | additions       diff --git a/The 90 Thing.tex b/The 90 Thing.tex  index 5f4bae2..737c6f1 100644  --- a/The 90 Thing.tex  +++ b/The 90 Thing.tex 
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\hline  n & prime? & num & fac\\  0 & 0 & 1 & 1 \\  1 & 0 & 91 & 7×13\\ %Failed  2 & 1 & (90;2)+1 & (90;2)+1 \\  3 & 1 & (90;3)+1 & (90;3)+1 \\  4 & 0 & ... & 7×13×19×52579 \\  5 & 0 & ... & 11×23×4093×8779 \\ %Failed  6 & 0 & ... & 859×1058313049 \\ %Failed  7 & 0 & ... & 7×13×211×241×2161×9091 \\  8 & 0 & ... & 103×4013×21993833369 \\ %Failed  9 & 1 & (90;9)+1 & (90;9)+1 \\  10 & 0 & ... & 7^2×13×127×2689×459691×909091 \\  11 & 0 & ... & 47×139×2531×549797184491917 \\ %Failed  12 & 0 & ... & 251×5051×9091×78875943472201 \\  13 & 0 & ... & 7×13×19×52579×70541929×14175966169 \\  14 & 0 & ... & 59×154083204930662557781201849 \\ %Failed  15 & 1 & (90;15)+1 & (90;15)+1 \\  16 & 0 & ... & 7×11×13×23×4093×8779×599144041×183411838171 \\  17 & 0 & ... & 9091×909091×4147571×265212793249617641 \\  18 & 0 & ... & 7253×422650073734453×296557347313446299 \\ %Failed  19 & 0 & ... & 7×13^2×157×859×6397×216451×1058313049×388847808493 \\  20 & 0 & ... & 2670502781396266997×3404193829806058997303 \\ %Failed  21 & 0 & ... & 57009401×2182600451×7306116556571817748755241 \\ %Failed  22 & 0 & ... & 7×13×19×211×241×2161×9091×29611×52579×3762091×8985695684401 \\  \end{array}  \end{equation} 
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However if one was going to search for a large prime in this form it would be wise to run this very quick check before hand. As in a matter of seconds one can tell that $(90;1000000076)+1$ may be prime, but $(90;1000000077)+1$ definately is not!  This is cute, as instead of cheking a number a billion digits long, we can check a number log_{10}(digits) in a linear way.  \section{Improving the algorithm...}  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... 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?  They don't feature a divisor of the form $(90;;n)+1$. Which was the main feature of the algorithm to rule numbers out. False numbers $0,1,5,6,8,11,14,18,20,21,23$. \\  Disregard $0$ as a special case. \\  Appears failure dues to very large primes, usually a product of two for example $n=14$, has 154083204930662557781201849 occurring.