Petersen family: 7 graphs
family[0]: n=6, m=15, degrees [5, 5, 5, 5, 5, 5]; cycles 197; unordered pairs of disjoint cycles 10
    (1) pairs of disjoint edges: 45; with N(e,f) odd: 0  -> sigma is an invariant of the graph
    (2) sigma on 12 random straight-line embeddings: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]; number of pairs with odd lk: [1, 1, 1, 1, 1, 3, 1, 3, 3, 1, 1, 1]
    => every embedding has a pair of disjoint cycles with odd linking number: True
family[1]: n=7, m=15, degrees [6, 4, 4, 4, 4, 4, 4]; cycles 150; unordered pairs of disjoint cycles 9
    (1) pairs of disjoint edges: 54; with N(e,f) odd: 0  -> sigma is an invariant of the graph
    (2) sigma on 12 random straight-line embeddings: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]; number of pairs with odd lk: [3, 3, 1, 1, 5, 1, 3, 3, 1, 1, 3, 1]
    => every embedding has a pair of disjoint cycles with odd linking number: True
family[2]: n=7, m=15, degrees [5, 5, 5, 4, 4, 4, 3]; cycles 151; unordered pairs of disjoint cycles 9
    (1) pairs of disjoint edges: 54; with N(e,f) odd: 0  -> sigma is an invariant of the graph
    (2) sigma on 12 random straight-line embeddings: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]; number of pairs with odd lk: [1, 1, 1, 5, 1, 1, 1, 1, 3, 1, 1, 3]
    => every embedding has a pair of disjoint cycles with odd linking number: True
family[3]: n=8, m=15, degrees [4, 4, 4, 4, 4, 4, 3, 3]; cycles 123; unordered pairs of disjoint cycles 9
    (1) pairs of disjoint edges: 63; with N(e,f) odd: 0  -> sigma is an invariant of the graph
    (2) sigma on 12 random straight-line embeddings: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]; number of pairs with odd lk: [1, 1, 1, 1, 3, 3, 3, 3, 1, 3, 1, 1]
    => every embedding has a pair of disjoint cycles with odd linking number: True
family[4]: n=8, m=15, degrees [5, 4, 4, 4, 4, 3, 3, 3]; cycles 113; unordered pairs of disjoint cycles 8
    (1) pairs of disjoint edges: 62; with N(e,f) odd: 0  -> sigma is an invariant of the graph
    (2) sigma on 12 random straight-line embeddings: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]; number of pairs with odd lk: [1, 1, 1, 1, 3, 1, 5, 1, 1, 1, 1, 3]
    => every embedding has a pair of disjoint cycles with odd linking number: True
family[5]: n=9, m=15, degrees [4, 4, 4, 3, 3, 3, 3, 3, 3]; cycles 82; unordered pairs of disjoint cycles 7
    (1) pairs of disjoint edges: 69; with N(e,f) odd: 0  -> sigma is an invariant of the graph
    (2) sigma on 12 random straight-line embeddings: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]; number of pairs with odd lk: [3, 1, 3, 1, 3, 3, 3, 1, 1, 1, 3, 3]
    => every embedding has a pair of disjoint cycles with odd linking number: True
family[6]: n=10, m=15, degrees [3, 3, 3, 3, 3, 3, 3, 3, 3, 3]; cycles 57; unordered pairs of disjoint cycles 6
    (1) pairs of disjoint edges: 75; with N(e,f) odd: 0  -> sigma is an invariant of the graph
    (2) sigma on 12 random straight-line embeddings: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]; number of pairs with odd lk: [1, 1, 1, 3, 3, 3, 3, 3, 1, 1, 1, 3]
    => every embedding has a pair of disjoint cycles with odd linking number: True
ALL SEVEN GRAPHS: True
