MapleSAT generating solutions that doesn't satisfy the constraint

[BrianLi009]

Given this cnf file: constraints_7.txt

Solve the instance using Maplesat-ks with the following command: ./maplesat-ks/simp/maplesat_static constraints_7.txt -order=7 -exhaustive=7.exhaust

The solver will output two solutions:

a -1 -2 -3 -4 -5 6 -7 8 -9 -10 11 -12 -13 -14 -15 16 17 18 19 20 21 0
a -1 -2 -3 -4 -5 6 -7 8 -9 -10 11 -12 13 14 -15 16 17 -18 -19 20 21 0

The 2nd solution does not satisfy the constraint, passing the 2nd solution to CaDiCaL would result in UNSAT.

[BrianLi009]

Here's how the cnf instance can be replicated if needed:

Remove the noncolorability and mindegree constraint from generate-conway.py. The part of the code calling different constraint functions should look like the following:

clause_count += squarefree(n, edge_dict, cnf_file)
print ("graph is squarefree")
clause_count += triangle(n, edge_dict, tri_dict, cnf_file)
print ("all vertices are part of a triangle")
var_count, c_count = cubic(n, count, cnf_file) 
clause_count += c_count
print ("isomorphism blocking applied")
var_count, c_count = conway(n, edge_dict, tri_dict, 1, 3, cnf_file, var_count) #at least 1 vertex is in 3 triangles
clause_count += c_count
print ("conway constraint")

Generate an instance with the following command: python3 gen_instance/generate-conway.py 7