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Numbers requiring 5 steps to reach a prime under the prime factor concatenation procedure.
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%I #9 Oct 15 2019 12:06:01

%S 14,34,147,164,183,214,216,230,236,248,252,276,285,309,324,335,404,

%T 405,444,482,484,486,508,520,527,540,550,570,580,633,636,638,658,689,

%U 704,730,738,802,814,852,915,935,954,959,960,981,996,1004,1037,1046,1058

%N Numbers requiring 5 steps to reach a prime under the prime factor concatenation procedure.

%H Patrick De Geest, <a href="http://www.worldofnumbers.com/topic1.htm">Home Primes</a>

%e 14 = 2*7 -> 27 = 3*3*3 -> 333 = 3*3*37 -> 3337 = 47*71 -> 4771 = 13*367 and 13367 is prime.

%Y Cf. A037271, A046411.

%K nonn,base

%O 0,1

%A _Patrick De Geest_, Jun 15 1998