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%I #13 Aug 13 2020 14:02:28
%S 127,347,2503,12101,12107,12109,15629,15641,15661,15667,15679,16381,
%T 16447,16759,16879,19739,21943,27653,28547,28559,29527,29531,32771,
%U 32783,35933,36457,39313,39343,43691,45361,46619,46633,46643,46649,46663,46691,48751,48757,49277,58921,59051,59053,59263,59273,64513,74353,74897,78163,83357
%N Prime Friedman numbers.
%C A Friedman number is one which is expressible in a nontrivial manner with the same digits by means of the arithmetic operations +, -, *, "divided by" along with ^ and digit concatenation.
%C Ron Kaminsky notes that, by Dirichlet's theorem, this sequence is infinite; see Friedman link. - _Charles R Greathouse IV_, Apr 30 2010
%C There are only 49 terms below 10^5, and there are less than 40 "orderly" terms (in A080035) below 10^6. - _M. F. Hasler_, Jan 03 2015
%H Erich Friedman, <a href="https://erich-friedman.github.io/mathmagic/0800.html">Problem of the Month (August 2000)</a>.
%F Intersection of A036057 and A000040. - _M. F. Hasler_, Jan 03 2015
%e Since the following primes have expressions 16381 = (1+1)^(6+8) - 3 ; 16447 = -1+64+4^7 ; 16759 = 7^5 - 6*(9-1), they are in the sequence.
%Y Cf. A036057.
%K nonn,base
%O 1,1
%A _Lekraj Beedassy_, Jan 23 2007
%E Corrected and extended by _Ray Chandler_, Apr 24 2010
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