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A080992
Entries in Dürer's magic square.
11
16, 3, 2, 13, 5, 10, 11, 8, 9, 6, 7, 12, 4, 15, 14, 1
OFFSET
1,1
COMMENTS
4 X 4 magic square included in Albrecht Dürer's 1514 engraving "Melancolia". 15 and 14 appear in the bottom row, giving the date.
From Reinhard Zumkeller, Jun 20 2013: (Start)
A006003(4) = 34 is the magic constant, occurring 23 times as sum of exactly 4 distinct numbers 1..16 with regular patterns in the 4 X 4 square (see also link).
Sum_{i = 1..4} T(k,i) = Sum_{i = 1..4} T(i,k) = 34, for k = 1..4;
Sum_{k = 1..4} T(k,k) = Sum_{k = 1..4} T(k,5-k) = 34;
T(1,1) + T(1,2) + T(2,1) + T(2,2) = 16 + 3 + 5 + 10 = 34;
T(1,3) + T(1,4) + T(2,3) + T(2,4) = 2 + 13 + 11 + 8 = 34;
T(3,1) + T(3,2) + T(4,1) + T(4,2) = 9 + 6 + 4 + 15 = 34;
T(3,3) + T(3,4) + T(4,3) + T(4,4) = 7 + 12 + 14 + 1 = 34;
T(1,1) + T(1,4) + T(4,1) + T(4,4) = 16 + 13 + 4 + 1 = 34;
T(2,2) + T(2,3) + T(3,2) + T(3,3) = 10 + 11 + 6 + 7 = 34;
T(1,2) + T(2,4) + T(4,3) + T(3,1) = 3 + 8 + 14 + 9 = 34;
T(1,3) + T(3,4) + T(4,2) + T(2,1) = 2 + 12 + 15 + 5 = 34;
T(1,2) + T(2,3) + T(4,2) + T(2,1) = 3 + 11 + 15 + 5 = 34;
T(1,3) + T(2,4) + T(4,3) + T(2,2) = 2 + 8 + 14 + 10 = 34;
T(1,2) + T(3,3) + T(4,2) + T(3,1) = 3 + 7 + 15 + 9 = 34;
T(1,3) + T(3,4) + T(4,3) + T(3,2) = 2 + 12 + 14 + 6 = 34;
T(1,2) + T(1,3) + T(4,2) + T(4,3) = 3 + 2 + 15 + 14 = 34;
T(4,2)*100 + T(4,3) = 1514, the year of the engraving and the pair (T(4,4),T(4,1)) = (1,4) corresponds to Albrecht Dürer's coded initials. (End)
The square has its magic constant (34) equal to one of its eigenvalues (34, 8, -8, 0) like any other normal magic square of order n > 2. - Michal Paulovic, Mar 14 2021
REFERENCES
Hossin Behforooz, "Permutation-free magic squares", J. Recreational Mathematics, vol. 33, (2004-2005), pp. 103-106.
LINKS
History 291, Princeton University, Durer's Melancolia
Laurence Eaves and Brady Haran, Magic square - Sixty Symbols
Eric Weisstein's World of Mathematics, Dürer's Magic Square
Eric Weisstein's World of Mathematics, Gnomon Magic Square
EXAMPLE
From Reinhard Zumkeller, Jun 20 2013: (Start)
1 2 3 4
+----+----+----+----+
1 | 16 | 3 | 2 | 13 |
+----+----+----+----+
2 | 5 | 10 | 11 | 8 |
+----+----+----+----+
3 | 9 | 6 | 7 | 12 |
+----+----+----+----+
4 | 4 | 15 | 14 | 1 |
+----+----+----+----+
D ^^ ^^ A (End)
CROSSREFS
Sequence in context: A031323 A095838 A040248 * A040249 A099143 A070709
KEYWORD
fini,full,nonn
AUTHOR
David W. Wilson, Feb 26 2003
STATUS
approved