|
%I #4 Feb 02 2021 22:15:49
%S -83,-53,-23,7,37,67,97,127,157
%N Primes p = -83 + n * 30 (n = 0, 1, ..., 8) forming "optimal" 3 x 3 Magic Prime Square.
%C 1st row: -53 157 7
%C 2nd row: 97 37 -23
%C 3rd row: 67 -83 127
%C Magic 3 x 3 square with minimal magic constant M = 3 * 37 = 111.
%C Elements are in arithmetic 1st-order progression, negative p are primes.
%C This magic prime square (MPS) from the author dates from 2008.
%C Note that Dudeney's MPS from 1917 has the nonprime element 1:
%C 67 1 43
%C 13 37 61
%C 31 73 7
%C Madachy/Ondrejka gave 1979 MPS with M = 3 * 59 = 177 > 111:
%C 17 89 71
%C 113 59 5
%C 47 29 101
%D E. Dudeney: Amusements in Mathematics, Problem 408, New York: Dover, 1970.
%D J. S. Madachy: Magic and Antimagic Squares, Madachy's Mathematical Recreations, New York, pp. 85-113, New York: Dover, 1979.
%D M. Miller: Geloeste und ungeloeste mathematische Probleme, Leipzig, 1982.
%Y Cf. A024351, A073519.
%K base,fini,uned,sign
%O 1,1
%A Ulrich Krug (leuchtfeuer37(AT)gmx.de), Mar 07 2010
|
