

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




OFFSET

1,1


COMMENTS

Leading zeros are forbidden in the rows and columns.


LINKS

Table of n, a(n) for n=1..8.


EXAMPLE

The 1 X 1 crosssquarepuzzle 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
Adjacent sequences: A105071 A105072 A105073 * A105075 A105076 A105077


KEYWORD

nonn,base,more


AUTHOR

Matthijs Coster, Apr 29 2005


EXTENSIONS

Corrected and extended by Luca Petrone, Jan 08 2017


STATUS

approved



