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A389665
Number of n X n grids with 2 non-attacking kings on each row.
2
1, 0, 0, 0, 0, 0, 0, 6, 1550, 988556, 587256692, 380941109984, 269426066012742, 209984659485901510, 181134684682770775026, 173170030245438700819026, 183363201875114562179890280, 214641442629841185419061952210, 277062451760356180321253082799576, 393235901044891675145321660768328072
OFFSET
0,8
LINKS
Hamidreza Maleki Tirabadi, Table of n, a(n) for n = 0..30
FORMULA
See A390419.
EXAMPLE
a(7) = 6. First solution is:
Row 1: [0, 2] -> * ° * ° ° ° °
Row 2: [4, 6] -> ° ° ° ° * ° *
Row 3: [0, 2] -> * ° * ° ° ° °
Row 4: [4, 6] -> ° ° ° ° * ° *
Row 5: [0, 2] -> * ° * ° ° ° °
Row 6: [4, 6] -> ° ° ° ° * ° *
Row 7: [0, 2] -> * ° * ° ° ° °
CROSSREFS
Column k=2 of A390419.
Cf. A389766.
Sequence in context: A265862 A378241 A281255 * A216934 A308029 A160226
KEYWORD
nonn
AUTHOR
STATUS
approved