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A221669
3 x 3 magic square containing seven squares, read by rows.
7
139129, 83521, 319225, 360721, 180625, 529, 42025, 277729, 222121
OFFSET
1,1
COMMENTS
Apart from trivial modifications, this is the only known 3 x 3 magic square containing seven squares. No 3 x 3 magic square containing eight or nine squares is known.
The seven integer square roots are A221670.
LINKS
A. Bremner, On squares of squares, Acta Arith. 88 (1999), 289-297.
A. Bremner, On squares of squares. II, Acta Arith. 99 (2001), 289-308.
John P. Robertson, Magic squares of squares, Math. Mag., 69 (1996), 289-293.
FORMULA
a(1) = 139129 = 373^2, a(2) = 83521 = 289^2, a(3) = 319225 = 565^2, a(5) = 180625 = 425^2, a(6) = 529 = 23^2, a(7) = 42025 = 205^2, a(8) = 277729 = 527^2.
EXAMPLE
[139129 83521 319225
360721 180625 529
42025 277729 222121]
CROSSREFS
Sequence in context: A250713 A236063 A234821 * A145207 A236745 A205213
KEYWORD
nonn,tabf,fini,full
AUTHOR
Jonathan Sondow, Jan 21 2013
STATUS
approved