cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A126078 Numbers such that the sum of the factorials of the digits of the fifth power is a square.

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