login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A187051 Number of 7-step one or two space at a time bishop's tours on an n X n board summed over all starting positions. 1
0, 0, 0, 400, 14024, 86608, 285048, 668176, 1272720, 2110944, 3180724, 4475176, 5989600, 7722744, 9674608, 11845192, 14234496, 16842520, 19669264, 22714728, 25978912, 29461816, 33163440, 37083784, 41222848, 45580632, 50157136, 54952360 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Row 7 of A187046.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..35

FORMULA

Empirical: a(n) = 109360*n^2 - 1219576*n + 3362248 for n>11.

Conjectures from Colin Barker, Apr 20 2018: (Start)

G.f.: 4*x^4*(100 + 3206*x + 11434*x^2 + 16724*x^3 + 14708*x^4 + 9182*x^5 + 3066*x^6 - 531*x^7 - 1721*x^8 - 1175*x^9 - 313*x^10) / (1 - x)^3.

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>14.

(End)

EXAMPLE

Some solutions for 4 X 4:

..0..1..0..3....0..2..0..0....0..2..0..7....0..3..0..7....0..7..0..0

..5..0..2..0....3..0..6..0....3..0..6..0....2..0..5..0....3..0..6..0

..0..4..0..7....0..5..0..1....0..5..0..1....0..6..0..4....0..4..0..1

..0..0..6..0....7..0..4..0....0..0..4..0....0..0..1..0....5..0..2..0

CROSSREFS

Cf. A187046.

Sequence in context: A192076 A006764 A108034 * A231288 A210262 A151608

Adjacent sequences:  A187048 A187049 A187050 * A187052 A187053 A187054

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 02 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 28 13:34 EST 2022. Contains 350656 sequences. (Running on oeis4.)