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A131636
List of impossible triples {V, F, E} that satisfy Euler's equation V=E-F+2 but do not correspond to polyhedra.
0
0, 2, 0, 0, 3, 1, 1, 1, 0, 1, 2, 1, 1, 3, 2, 2, 0, 0, 2, 1, 1, 2, 2, 2, 2, 3, 3, 3, 0, 1, 3, 1, 2, 3, 2, 3, 3, 3, 4
OFFSET
1,2
COMMENTS
This set of triples seems to be a finite set of "graphs" that are Euler solutions but not polyhedra.
FORMULA
If V<4 and F<4 and E<7 and V=E-F+2: a(n) = {V(m),F(m),E(m)}
MATHEMATICA
a = Delete[Union[Flatten[Table[If[v + f - 2 - e0 == 0, {v, f, e0}, {}], {v, 0, 3}, {f, 0, 3}, {e0, 0, 6}], 2]], 1]; Flatten[a]
CROSSREFS
Cf. A130840.
Sequence in context: A351592 A082660 A134673 * A188023 A077888 A319668
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Sep 05 2007
EXTENSIONS
Partially edited by N. J. A. Sloane, Sep 14 2007.
STATUS
approved