A231351 - OEIS

%I #7 Dec 21 2013 04:15:59

%S 1,2,2,2,4,5,4,2,4,6,8,5,10,11,8,2,4,6,8,6,12,14,16,5,10,14,20,11,22,

%T 23,16,2,4,6,8,6,12,14,16,6,12,16,24,14,28,30,32,5,10,14,20,14,28,32,

%U 40,11,22,30,44,23,46,47,32,2,4,6,8,6,12,14,16

%N a(n) = A231349(n+1)/2.

%C Observation: the row sums of the first six rows coincide with the first six elements of A006234.

%C Is A006234 the row sums of this triangle?

%H N. J. A. Sloane, <a href="/wiki/Catalog_of_Toothpick_and_CA_Sequences_in_OEIS">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a>

%e Written as an irregular triangle in which row lengths is A000079 the sequence begins:

%e 1;

%e 2,2;

%e 2,4,5,4;

%e 2,4,6,8,5,10,11,8;

%e 2,4,6,8,6,12,14,16,5,10,14,20,11,22,23,16;

%e 2,4,6,8,6,12,14,16,6,12,16,24,14,28,30,32,5,10,14,20,14,28,32,40,11,22,30,44,23,46,47,32;

%Y Right border gives A000079.

%Y Cf. A006234, A231348, A231349.

%K nonn,tabf

%O 1,2

%A _Omar E. Pol_, Dec 17 2013