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 A271581 #8 Apr 14 2016 10:05:35 %S A271581 251,305,317,341,362,366,371,377,387,389,410,421,427,431,434,435,440, %T A271581 446,455,458,470,482,483,484,490,494,497,500,506,512,515,519,521,523, %U A271581 525,536,546,547,548,550,551,553,563,566,572,575,578,580,584,586,590,591 %N A271581 Magic sums of 4 X 4 magic squares composed of triangular numbers and squares. %H A271581 <a href="/index/Mag#magic">Index entries for sequences related to magic squares</a> %e A271581 Examples of 4 X 4 magic squares composed of triangular numbers and squares. %e A271581 . %e A271581 |---|---|---|---| %e A271581 | 6 | 10|210| 25| %e A271581 |---|---|---|---| %e A271581 | 81|121| 21| 28| %e A271581 |---|---|---|---| %e A271581 | 64|105| 4 | 78| %e A271581 |---|---|---|---| %e A271581 |100| 15| 16|120| %e A271581 |---|---|---|---| %e A271581 The magic constant is 251 = a(1). %e A271581 . %e A271581 |---|---|---|---| %e A271581 | 4 | 10| 81|210| %e A271581 |---|---|---|---| %e A271581 |105|144| 55| 1 | %e A271581 |---|---|---|---| %e A271581 |171| 15| 91| 28| %e A271581 |---|---|---|---| %e A271581 | 25|136| 78| 66| %e A271581 |---|---|---|---| %e A271581 The magic constant is 305 = a(2). %Y A271581 Cf. A271578, A271579. %K A271581 nonn %O A271581 1,1 %A A271581 _Arkadiusz Wesolowski_, Apr 10 2016