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A187860 Number of 5-step one space for components leftwards or up, two space for components rightwards or down asymmetric quasi-queen's tours (antidiagonal moves become knight moves) on an n X n board summed over all starting positions. 1
0, 0, 486, 3320, 11986, 26836, 50378, 81124, 120051, 166504, 220483, 281988, 351019, 427576, 511659, 603268, 702403, 809064, 923251, 1044964, 1174203, 1310968, 1455259, 1607076, 1766419, 1933288, 2107683, 2289604, 2479051, 2676024, 2880523 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Row 5 of A187857.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..50

FORMULA

Empirical: a(n) = 3763*n^2 - 25044*n + 40644 for n>7.

Conjectures from Colin Barker, Apr 26 2018: (Start)

G.f.: x^3*(486 + 1862*x + 3484*x^2 + 352*x^3 + 2508*x^4 - 1488*x^5 + 977*x^6 - 655*x^7) / (1 - x)^3.

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>10.

(End)

EXAMPLE

Some solutions for 4 X 4:

..0..1..0..0....0..0..2..0....0..0..0..0....0..0..5..0....0..0..0..0

..0..0..0..4....0..0..1..0....1..0..0..0....4..1..0..0....0..4..3..5

..0..2..0..3....5..4..3..0....5..0..0..0....0..3..0..0....0..0..2..0

..0..0..5..0....0..0..0..0....4..3..2..0....0..2..0..0....0..0..0..1

CROSSREFS

Cf. A187857.

Sequence in context: A249227 A130181 A158325 * A205240 A206146 A128969

Adjacent sequences:  A187857 A187858 A187859 * A187861 A187862 A187863

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 14 2011

STATUS

approved

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Last modified December 5 10:11 EST 2021. Contains 349543 sequences. (Running on oeis4.)