A109252 Number of fair sudoku problems with n given values on a 4 x 4 grid.

0, 0, 0, 0, 25728, 284160, 1041408, 2141184, 2961024, 2958336, 2204928, 1239552, 522624, 161280, 34560, 4608, 288

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