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 A025051 #17 Jun 25 2024 11:41:01
%S A025051 3,5,7,8,9,11,12,13,14,15,16,17,19,20,21,23,24,25,26,27,28,29,31,32,
%T A025051 33,34,35,36,37,38,39,40,41,43,44,45,46,47,48,49,50,51,52,53,54,55,56,
%U A025051 57,59,60,61,62,63,64,65,66,67,68,69,71,72,73,74,75,76,77,79,80,81,82,83,84,85,86,87,88
%N A025051 Numbers of the form j*k + k*i + i*j, where i,j,k >= 1.
%H A025051 J. Borwein and K.-K. S. Choi, <a href="http://projecteuclid.org/euclid.em/1046889597">On the representations of xy+yz+zx</a>, Experimental Mathematics, 9 (2000), 153-158.
%H A025051 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).
%F A025051 On the GRH, a(n) = n + 18 for n > 444. If there is some N > 444 with a(N) not equal to n + 19, then for n >= N, a(n) = n + 19 (and GRH is false). See Borwein & Choi. - _Charles R Greathouse IV_, Dec 19 2022
%F A025051 n is in the sequence if and only if A066955(n) > 0. - _Charles R Greathouse IV_, Jun 25 2024
%t A025051 Take[Union[Total[Times@@@Subsets[#,{2}]]&/@Tuples[Range[25],{3}]], 80] (* _Harvey P. Dale_, Aug 11 2011 *)
%Y A025051 Uniquification of sequence A025050.
%Y A025051 Cf. A025052 (complement), A066955.
%K A025051 nonn,nice,easy
%O A025051 1,1
%A A025051 _Clark Kimberling_