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A187609
Number of 5-step one space for components leftwards or up, two space for components rightwards or down asymmetric quasi-bishop's tours (antidiagonal moves become knight moves) on an n X n board summed over all starting positions.
1
0, 0, 0, 8, 130, 500, 1274, 2372, 3953, 5920, 8273, 11012, 14137, 17648, 21545, 25828, 30497, 35552, 40993, 46820, 53033, 59632, 66617, 73988, 81745, 89888, 98417, 107332, 116633, 126320, 136393, 146852, 157697, 168928, 180545, 192548, 204937
OFFSET
1,4
COMMENTS
Row 5 of A187606.
LINKS
FORMULA
Empirical: a(n) = 193*n^2 - 1700*n + 3620 for n>7.
Conjectures from Colin Barker, Apr 25 2018: (Start)
G.f.: x^4*(8 + 106*x + 134*x^2 + 156*x^3 - 80*x^4 + 159*x^5 - 97*x^6) / (1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>10.
(End)
EXAMPLE
Some solutions for 5 X 5:
..0..0..0..0..0....0..0..5..0..0....0..0..2..0..0....0..0..0..5..0
..0..0..3..0..0....0..0..0..4..0....4..0..0..1..0....0..1..0..0..4
..2..0..0..5..0....0..0..0..0..3....0..3..0..0..0....0..0..3..0..0
..0..1..0..0..4....0..0..2..0..0....0..0..5..0..0....0..0..0..2..0
..0..0..0..0..0....1..0..0..0..0....0..0..0..0..0....0..0..0..0..0
CROSSREFS
Cf. A187606.
Sequence in context: A239756 A295240 A240630 * A365058 A241076 A349683
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 11 2011
STATUS
approved