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A169778 a(n) = ceiling(A170905/2). 2
0, 1, 1, 1, 2, 1, 2, 3, 4, 1, 2, 3, 5, 5, 4, 7, 8, 1, 2, 3, 5, 5, 5, 9, 13, 9, 4, 7, 12, 14, 10, 16, 16, 1, 2, 3, 5, 5, 5, 9, 13, 9, 5, 9, 15, 19, 17, 21, 29, 17, 4, 7, 12, 14, 14, 22, 34, 30, 14, 16, 28, 35, 25, 35, 32, 1, 2, 3, 5, 5, 5, 9, 13, 9, 5, 9, 15, 19, 17, 21 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

The hexagon-based CA of A151723 has as symmetry group the dihedral group of order 12. Consider a one-twelfth slice; a(n) is the number of cells that are turned from OFF to ON at generation n.

LINKS

Table of n, a(n) for n=0..79.

FORMULA

A170905(n) = 2a(n) except A170905(1)=1.

EXAMPLE

Illustration of generations 1 through 9:

.1

..2

...3

..4.4

.....5

..7.6.6

...7...7

..8.8.8.8

.........9

...

From Omar E. Pol, Feb 12 2013: (Start)

When written as a triangle from 1, the right border gives A011782 and row lengths give A011782.

1,

1,

1,2,

1,2,3,4,

1,2,3,5,5,4,7,8,

1,2,3,5,5,5,9,13,9,4,7,12,14,10,16,16,

1,2,3,5,5,5,9,13,9,5,9,15,19,17,21,29,17,4,7,12,14,14,22,34,30,14,16,28,35,25,35,32;

1,2,3,5,5,5,9,13,9,5,9,15,19,17,21,... (End)

CROSSREFS

Cf. A151723, A151724, A170905.

Sequence in context: A062050 A233782 A233972 * A255560 A046653 A162190

Adjacent sequences:  A169775 A169776 A169777 * A169779 A169780 A169781

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane, May 08 2010

STATUS

approved

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Last modified March 25 13:37 EDT 2017. Contains 284081 sequences.