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A080035 "Orderly" Friedman numbers (or "good" Friedman numbers): Friedman numbers (A036057) where the construction digits are used in the proper order. 7

%I

%S 127,343,736,1285,2187,2502,2592,2737,3125,3685,3864,3972,4096,6455,

%T 11264,11664,12850,13825,14641,15552,15585,15612,15613,15617,15618,

%U 15621,15622,15623,15624,15626,15632,15633,15642,15645,15655,15656

%N "Orderly" Friedman numbers (or "good" Friedman numbers): Friedman numbers (A036057) where the construction digits are used in the proper order.

%C Primes in this sequence are listed in A252483. The subsequence A156954 is a "simplified" variant where no parentheses, unary operations (negation) nor concatenation is allowed. - _M. F. Hasler_, Jan 07 2015

%D Credit goes to Mike Reid (Brown University) and Eric Friedman (Stetson University).

%D Colin Rose, "Radical Narcissistic numbers", J. Recreational Mathematics, vol. 33, (2004-2005), pp. 250-254. See page 251.

%H M. Brand, <a href="http://dx.doi.org/10.1016/j.dam.2013.05.027">Friedman numbers have density 1</a>, Discrete Applied Mathematics, Volume 161, Issues 16-17, November 2013, Pages 2389-2395.

%H Ed Copeland and Brady Haran, <a href="https://www.youtube.com/watch?v=I7v2wAXFQpc">Friedman numbers</a>, Numberphile video, 2014

%H Eric Friedman, <a href="http://www.stetson.edu/~efriedma/mathmagic/0800.html">Friedman Numbers</a>.

%H Robert G. Wilson v, <a href="/A080035/a080035.txt">Table of n, a(n) for n = 1..108 </a>.

%e 127 = -1 + 2^7, 343 = (3 + 4) ^ 3, 736 = 7 + 3^6, etc.

%e The 4th "orderly" Freidman number is 1285 = (1 + 2^8) * 5.

%Y Cf. A036057.

%K nonn,base,nice

%O 1,1

%A David Rattner (david_rattner(AT)prusec.com), Mar 14 2003

%E More terms from _Alonso del Arte_, Aug 25 2004

%E Edited by _M. F. Hasler_, Jan 07 2015

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Last modified July 15 14:39 EDT 2018. Contains 312638 sequences. (Running on oeis4.)