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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.

A164843 The smallest magic constant of an n X n magic square with distinct prime entries.

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%I A164843 #15 Feb 16 2025 08:33:11
%S A164843 177,120,233,432,733,1154,1731,2470,3417,4584,6013,7712,9731,12088,
%T A164843 14807,17940,21501,25530,30021,35086,40675,46840,53631,61092,69251,
%U A164843 78100,87697,98084,109309,121380,134377,148258,163043
%N A164843 The smallest magic constant of an n X n magic square with distinct prime entries.
%C A164843 a(n) >= m(n), where m(n) is the smallest integer of the same parity as n, which is >= (Sum_{k=1..n^2} prime(k+1))/n. For example, Sum_{k=1..5^2} prime(k+1)/5=231.8, so m(5)=233. Conjecture: for n > 4, a(n)=m(n) or a(n)=m(n)+2.
%H A164843 Harvey Heinz, <a href="http://www.magic-squares.net/primesqr.htm">Prime magic squares</a>
%H A164843 A. Lelechenko and N. Makarova, <a href="/A164843/a164843.txt">Examples of prime magic n X n squares with minimal magic constant for n=5..13.</a>
%H A164843 N. Makarova, <a href="http://www.natalimak1.narod.ru/sqmin1.htm">Smallest prime magic squares, Part I</a> (in Russian)
%H A164843 N. Makarova, <a href="http://www.natalimak1.narod.ru/sqmin2.htm">Smallest prime magic squares, Part II</a> (in Russian)
%H A164843 Mathworld, <a href="https://mathworld.wolfram.com/PrimeMagicSquare.html">Prime magic squares</a>
%H A164843 PlanetMath, <a href="http://planetmath.org/encyclopedia/PrimeMagicSquare.html">Prime magic squares</a>
%H A164843 Stefano Tognon, <a href="http://digilander.libero.it/ice00/magic/prime/PrimeAnalysis.html">Prime Analysis</a>
%e A164843 From _Natalia Makarova_, Sep 26 2009: (Start)
%e A164843 Here is a 14 X 14 example:
%e A164843   [  3   43   59  131  181  271  383  599  797  919  971 1039 1123 1193
%e A164843   1151  433  967  211  337  491  397  691   83  523  593  773  449  613
%e A164843    263  373  101 1063  877  617  419  911  787  241  151  839  739  331
%e A164843    503  439  809 1051 1091  659  157 1031   71  139  379  179  743  461
%e A164843    173  647 1069  389 1049   19  311  223  317 1103  283  947  499  683
%e A164843    547   13 1061  353  229  853  677  751  571  983 1201   29  193  251
%e A164843    643  269  887  733   23  409 1129  191  769  401   47 1109  149  953
%e A164843    163  881  673  107  431  487  991  631  829  109  349  367  811  883
%e A164843   1163  827  607 1171  443  653  463    5  457  577   31  293  601  421
%e A164843    509 1097  313  757  167  709  761  347  857  137  619  233   89 1117
%e A164843   1093 1019    7  521 1033   61   73  941 1009  859  701   11  127  257
%e A164843     53  467   97  307 1153  557 1021  569  359  937  821  113  977  281
%e A164843    907   17  823  641  661  929   67  719   79  587  479  563 1013  227
%e A164843    541 1187  239  277   37  997  863  103  727  197 1087 1217  199   41 ]
%e A164843 (End)
%e A164843 Comment from _N. J. A. Sloane_, Sep 28 2009: this contains 192 consecutive primes, 3 to 1171, plus 1187, 1193, 1201, 1217.
%e A164843 For the 3 X 3 case see A024351. For the 4 X 4 magic square see the Mathworld link.
%Y A164843 Cf. A073502, A073350, A125007.
%K A164843 nonn,more
%O A164843 3,1
%A A164843 _Andrew Lelechenko_, Aug 28 2009 and _Natalia Makarova_, Sep 08 2009
%E A164843 Partially reworded by _R. J. Mathar_, Aug 31 2009
%E A164843 Edited by _N. J. A. Sloane_, Sep 14 2009
%E A164843 a(11)-a(15) from _Natalia Makarova_, a(16)-a(35) from _Natalia Makarova_ and Stefano Tognon
%E A164843 Edited by _Max Alekseyev_, Feb 11 2010