Steps To Reproduce

With SageMath version 10.6.beta6, Release Date: 2025-02-10, I observe:

sage: G1 = Graph( [(0, 1), (0, 2), (0, 3), (0, 4), (1, 2), (1, 3),
....: (1, 5), (2, 3), (2, 4), (3, 5), (4, 6), (4, 7), (5, 6), (5, 7), (6, 8),
....: (6, 10), (7, 9), (7, 11), (8, 9), (8, 10), (9, 11), (10, 11)])
sage: claw = graphs.ClawGraph()
sage: it = G1.subgraph_search_iterator(claw, return_graphs=False)
sage: next(it)
[10, 6, 8, 11]
sage: next(it)
[10, 6, 11, 8]
sage: next(it)
[10, 8, 6, 11]
sage: next(it)
[10, 8, 11, 6]
sage: next(it)
[10, 11, 6, 8]
...

Expected Behavior

The iterator should not yield many copies of the same subgraph.

Actual Behavior

We observe that the same subgraph is returned many times by the search iterator (up to a permutation of the vertices).

Additional Information

Observed during #39598

Environment

• OS: Ubuntu 22.04
• Sage Version: SageMath version 10.6.beta6, Release Date: 2025-02-10

Checklist

• I have searched the existing issues for a bug report that matches the one I want to file, without success.
• I have read the documentation and troubleshoot guide