A178573 Number of exposed endpoints in the toothpick structure of A182840.

2, 4, 8, 8, 8, 12, 20, 16, 8, 12, 24, 32, 28, 28, 44, 32, 8, 12, 24, 32, 32, 40, 64, 72, 44, 28, 56, 84, 80, 72, 100, 64, 8, 12, 24, 32, 32, 40, 64, 72, 48, 40, 72, 112, 120, 112, 144, 152, 76, 28, 56, 84

Offset: 1

Author

Olaf Voß, Dec 24 2010

Keywords

• nonn

Examples

			At stage 1 we place a toothpick anywhere in the plane (for example, in vertical position). There are two exposed endpoints, so a(1)=2.
At stage 2 we place 4 toothpicks: two new toothpicks touching each exposed endpoint. There are now 4 exposed endpoints, so a(2)=4.
		

Links

• N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS
• Olaf Voß, Toothpick structures on hexagonal net
• Index entries for sequences related to toothpick sequences