A222181 Number of pentagons added at n-th stage to the structure of A222180.

0, 1, 5, 10, 10, 10, 20, 30, 20, 10, 20, 40, 40, 30, 50, 70, 40, 10, 20, 40, 60, 80

Offset: 0

Author

Omar E. Pol, Mar 15 2013

Keywords

• nonn
• tabf
• more

Comments

Essentially the first differences of A222180.

Also number of P-toothpicks added at n-th stage to the P-toothpick structure of A222180.

Examples

			Apparently this is an irregular triangle:
0;
1;
5;
10,10;
10,20,30,20;
10,20,40,40,30,50,70,40;
10,20,40,60,80,...
		

Links

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

Crossrefs

Cf. A139250, A139251, A147582, A151724, A152968, A161645, A182633, A182841, A222173, A222177, A222180.

Formula

a(n) = 10*A222173(n-2), n >= 3. - Omar E. Pol, Nov 24 2013