A300694 a(n) = number of edges in a cocoon concertina n-cube.

0, 1, 13, 139, 1605, 20741

Offset: 0

Author

Tilman Piesk, Mar 24 2018

Keywords

• nonn
• more

Comments

n-place formulas in first-order logic like Ax Ey P(x, y) or Ex P(x, x) can be ordered by implication. This Hasse diagram has A300696(n) vertices and a(n) edges.

The corresponding sequence for convex concertina n-cubes is A300693.

Examples

			The cocoon concertina square has the A300693(2) = 6 outer and 7 inner edges, giving a(n) = 13 in total.
		

Links

• Tilman Piesk, Formulas in predicate logic (Wikiversity)
• Tilman Piesk, Image of a cocoon concertina square with 13 edges
• Tilman Piesk, Lists of edges for n=2..5
• Tilman Piesk, Python code used to generate the sequence

Crossrefs

Cf. A300696, A300693.