OFFSET
0,2
COMMENTS
Number of 1's in n-th row of triangle in A070950.
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 0..10000
N. J. A. Sloane, Illustration of first 20 generations
N. J. A. Sloane, On the Number of ON Cells in Cellular Automata, arXiv:1503.01168 [math.CO], 2015.
Eric Weisstein's World of Mathematics, Rule 30
Wikipedia, Rule 30
EXAMPLE
May be arranged into blocks of length 1,1,2,4,8,16,...:
1,
3,
3, 6,
4, 9, 5, 12,
7, 12, 11, 14, 12, 19, 13, 22,
15, 19, 20, 24, 21, 23, 23, 28, 26, 27, 26, 33, 30, 34, 31, 39,
26, 39, 29, 46, 32, 44, 38, 45, 47, 41, 45, 49, 38, 55, 42, 51,
44, 53, 43, 59, 52, 60, 49, 65, 57, 60, 56, 69, 61, 70, 59, 78,
64, 56, 65, 69, 69, ...
MATHEMATICA
Map[Function[Apply[Plus, Flatten[ #1]]], CellularAutomaton[30, {{1}, 0}, 100]] (* N. J. A. Sloane, Aug 10 2009 *)
SequenceCount[s, {1, 0}] + 2 SequenceCount[s, {0, 0, 1}] (* gives a(n) where s is the sequence for row n-1 *) (* Trevor Cappallo, May 01 2021 *)
PROG
(Haskell)
a070952 = sum . a070950_row -- Reinhard Zumkeller, Jun 07 2013
CROSSREFS
KEYWORD
nonn,easy,nice
AUTHOR
N. J. A. Sloane, May 19 2002, Aug 10 2009
EXTENSIONS
More terms from Hans Havermann, May 26 2002
Corrected offset and initial term - N. J. A. Sloane, Jun 07 2013
STATUS
approved