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%I #11 Jan 29 2015 10:33:05
%S 1,2,4,5,6,7,9,11,13,15,16,27,31,33,36,55,73,91,133,241,249,366,367,
%T 491,513,577,733,757,871,913,971,991,1233,1333,1576,1711,1927,2071,
%U 2346,2593,2731,3307,3391,3529,4005,4591,5113,5371,5409,5671,5793,6567,6801,7465,7591
%N Numbers n such that (n^n-3)/(n-3) is an integer.
%C For n > 6, equivalent to n such that n^n = 3 mod n-3. - _Chai Wah Wu_, Jan 19 2015
%H Chai Wah Wu, <a href="/A242788/b242788.txt">Table of n, a(n) for n = 1..4388</a>
%e (6^6-3)/(6-3) = 46653/3 = 15551 is an integer. Thus 6 is a member of this sequence.
%t Select[ Range@ 7600, Mod[ PowerMod[#, #, # - 3] - 3, # - 3] == 0 &] (* _Robert G. Wilson v_, Jan 21 2015 *)
%o (PARI) for(n=1,10^4,if(n!=3,s=(n^n-3)/(n-3);if(floor(s)==s,print(n))))
%o (Python)
%o A242788_list = [1,2,4,5,6] + [n for n in range(7,10**6) if pow(n, n, n-3) == 3]
%o # _Chai Wah Wu_, Jan 19 2015
%Y Cf. A242787.
%K nonn
%O 1,2
%A _Derek Orr_, May 22 2014
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