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%I #9 Jul 22 2017 23:44:55
%S 729,1296,1764,2378,2744,2746,3645,4372,4374,4913,5184,6495,6859,8192
%N Radical narcissistic numbers: numbers n that can be expressed using just the digits of n (each digit used once only and in order from left to right) and the operators + - * / ^ and the radical symbol, but which are not already 'Good' Friedman numbers (i.e., the radical is needed for the solution to exist). Concatenation is allowed.
%C There are only 14 radical narcissistic integers n < 10000.
%D J. S. Madachy, Mathematics on Vacation, Thomas Nelson and Sons, (1966), pp. 163 - 175.
%D Colin Rose, "Radical Narcissistic numbers", J. Recreational Mathematics, vol. 33, (2004-2005), pp. 250-254.
%H C. Rose, <a href="http://www.numq.com/pwn/">Pretty Wild Narcissistic Numbers - numbers that pwn</a> (2006)
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Friedman_number">Friedman number</a>
%e 729 = (7 + 2)^sqrt(9);
%e 2378 = -23 + sqrt(7^8).
%t Mathematica code to be available at: http://www.numq.com/pwn/
%Y Cf. A080035.
%K base,nonn
%O 1,1
%A _Colin Rose_, Jun 10 2006
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