A109459 Number of inequivalent Krom functions on n variables (or 2SAT instances) under permuting and complementing variables.

2, 3, 6, 14, 45, 196, 1360, 15631

Offset

0,1

References

Knuth, Donald E., Satisfiability, Fascicle 6, volume 4 of The Art of Computer Programming. Addison-Wesley, 2015, pages 148 and 220, Problem 191.

Links

Table of n, a(n) for n=0..7.

Crossrefs

See A109457 for definitions and references.

Sequence in context: A056569 A094468 A091285 * A118986 A091138 A335260

Adjacent sequences: A109456 A109457 A109458 * A109460 A109461 A109462

Keyword

nonn,hard,more

Author

Don Knuth, Aug 24 2005

Status

approved