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%I #15 Mar 29 2014 14:46:33
%S 1,396,849,1000,2807,4274,4565,4971,5000,6030,6487,6942,7281,8210,
%T 11163,11847,11895,15015,17682,19043,19584,19586,20500,20577,20957,
%U 21315,23000,23188,23397,25747,27121,27720,29241,29399,32160,34233,35234
%N Numbers such that the sum of the factorials of the digits of the fifth power is a square.
%H Vincenzo Librandi, <a href="/A126078/b126078.txt">Table of n, a(n) for n = 1..534</a>
%e a(2) = 396, 396^5 = 9738138110976, 9! + 7! + 3! + 8! + 1! + 3! + 8! + 1! + 1! + 0! + 9! + 7! + 6! = 817216 = 904^2.
%p a:=proc(n) local nn: nn:=convert(n^5,base,10): if type(sqrt(add(nn[j]!,j=1..nops(nn))),integer)=true then n else fi end: seq(a(n),n=1..45000); # _Emeric Deutsch_, Mar 06 2007
%t Select[Range[50000], IntegerQ[Sqrt[Total[IntegerDigits[#^5]!]]]&] (* _Vincenzo Librandi_, Mar 29 2014 *)
%K nonn,base
%O 1,2
%A _Yalcin Aktar_, Mar 02 2007
%E More terms from _Emeric Deutsch_, Mar 06 2007
%E Name changed by _Franklin T. Adams-Watters_, Mar 29 2014
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