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.
%I A082875 #9 Oct 01 2013 17:57:38
%S A082875 4,9,36,49,841,5184
%N A082875 Squares that are the sum of three factorials.
%F A082875 a1! + a2! + a3! = z^2.
%e A082875 These appear to be the only solutions. 8 and 27 appear to be the only cubes that are the sum of 3 factorials. Again, it appears that 2 and 3 are the only powers of n satisfying a1!+a2!+a3! = z^n.
%e A082875 The complete list of solutions is
%e A082875 a1 a2 a3 z^2
%e A082875 0 0 2 4
%e A082875 0 1 2 4
%e A082875 0 2 3 9
%e A082875 0 4 4 49
%e A082875 0 5 6 841
%e A082875 1 1 2 4
%e A082875 1 2 3 9
%e A082875 1 4 4 49
%e A082875 1 5 6 841
%e A082875 3 3 4 36
%e A082875 4 5 7 5184
%t A082875 d = 50; a = Union[ Flatten[ Table[a! + b! + c!, {a, 1, d}, {b, a, d}, {c, b, d}]]]; l = Length[a]; Do[ If[ IntegerQ[ Sqrt[ a[[i]]]], Print[ a[[i]]]], {i, 1, l}]
%o A082875 (PARI) sum3factsq(n) = { for(a1=1,n, for(a2=a1,n, for(a3=a2,n, z = a1!+a2!+a3!; if(issquare(z),print1(z" ")) ) ) ) }
%Y A082875 Cf A114377, A162681.
%K A082875 easy,nonn
%O A082875 1,1
%A A082875 _Cino Hilliard_, May 25 2003
%E A082875 Sequence data ordered by _Michel Marcus_, Jun 03 2013