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%I #20 Feb 14 2021 14:54:28
%S 1005,5405,89195,92029,107707,149851,323723,524371,610171,999643,
%T 1119253,1134227,1728787,1900523,2045171,2170451,2668381,3351833,
%U 3361717,3611227,5364059,6571483,7710883,7865659,8938691,9286331,9362051,9593833,10841387,11507813
%N Numbers k such that the sum of digits^4 of k equals Sum_{d|k, 1<d<k} d.
%C The sequence is finite because the restricted sum of divisors of n, for n composite, is at least sqrt(n), while the sum of the fourth powers of the digits of n is at most 9^4*log_10(n+1). Last term is a(101) = 163998389. - _Giovanni Resta_, Oct 05 2018
%H Giovanni Resta, <a href="/A202147/b202147.txt">Table of n, a(n) for n = 1..101</a> (full sequence)
%e 1005 is in the sequence because 1^4 + 0^4 + 0^4 + 5^4 = 626, and the sum of the divisors 1< d<1005 is 3 + 5 +15 + 67 + 201+ 335 = 626.
%t Q[n_]:=Module[{a=Total[Rest[Most[Divisors[n]]]]}, a == Total[IntegerDigits[n]^4]]; Select[Range[2, 10^7], Q]
%Y Cf. A070308, A202279, A202285, A202240.
%K nonn,base,fini,full
%O 1,1
%A _Michel Lagneau_, Dec 15 2011
%E Keywords fini and full added by _Giovanni Resta_, Oct 05 2018
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