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A105074
Number of ways to fill in an n X n grid such that the digits of each row and each column form a square number.
1
3, 4, 13, 14, 76, 108, 459, 844
OFFSET
1,1
COMMENTS
Leading zeros are forbidden in the rows and columns.
EXAMPLE
The 1 X 1 crosssquare-puzzle is easy; the only solutions are 1, 4, and 9.
The 4 solutions for n=2 are [16/64], [36/64], [64/49], [81/16].
Or, writing them as 2 X 2 matrices,
16 36 64 81
64 64 49 16
CROSSREFS
Sequence in context: A095790 A109474 A053910 * A208847 A278426 A293280
KEYWORD
nonn,base,more
AUTHOR
Matthijs Coster, Apr 29 2005
EXTENSIONS
Corrected and extended by Luca Petrone, Jan 08 2017
STATUS
approved