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A109252 Number of fair sudoku problems with n given values on a 4 x 4 grid. 0
0, 0, 0, 0, 25728, 284160, 1041408, 2141184, 2961024, 2958336, 2204928, 1239552, 522624, 161280, 34560, 4608, 288 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

A problem is 'fair' if the given values are sufficient to resolve the entire grid to a unique Sudoku solution. Since a(16) represents problems in which the whole grid is already given, a(16) is necessarily the same as A107739(2).

LINKS

Table of n, a(n) for n=0..16.

EXAMPLE

An example fair problem with 4 given digits is ?4?2 / ???1 / ???? / ?3??, which has the complete grid 1432 / 3241 / 4123 / 2314 as the only solution. There are 25,728 such fair problems with 4 given digits, so a(4) = 25728.

CROSSREFS

Cf. A107739.

Sequence in context: A172946 A237478 A115535 * A142708 A224575 A237962

Adjacent sequences:  A109249 A109250 A109251 * A109253 A109254 A109255

KEYWORD

fini,full,nonn

AUTHOR

Hugo van der Sanden, Aug 19 2005

STATUS

approved

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Last modified October 2 05:15 EDT 2022. Contains 357191 sequences. (Running on oeis4.)