A220525 Number of toothpicks or D-toothpicks added at n-th stage to the structure of A220524.

0, 1, 2, 4, 4, 4, 8, 11, 8, 4, 8, 16, 24, 16, 20, 25, 16, 4, 8, 16, 24, 32, 36, 42, 44, 20, 24, 44, 64, 40, 44, 53, 32, 4, 8, 16, 24, 32, 36, 44, 52, 42, 48, 64, 100, 80, 84, 91, 84, 28, 24, 48, 72, 92, 104, 124, 132, 54, 56, 100, 144, 88, 92, 109, 64, 4

Offset: 0

Author

Omar E. Pol, Mar 23 2013

Keywords

• nonn
• tabf

Comments

Essentially the first differences of A220524.

First differs from A194445 at a(13).

Examples

			When written as an irregular triangle begins:
0;
1;
2;
4,4;
4,8,11,8;
4,8,16,24,16,20,25,16;
4,8,16,24,32,36,42,44,20,24,44,64,40,44,53,32;
4,8,16,24,32,36,44,52,42,48,64,100,80,84,91,84,28,24,48,72,92,104,124,132,54,56,100,144,88,92,109,64;
		

Links

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

Crossrefs

Row lengths give 1 together with A011782. Right border gives 0 together with A000079.

Cf. A139251, A194701, A194445, A220501, A220521, A220524, A220527.

Formula

a(n) = A221528(n)/4.