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A172313
a(n) = A172309(n+1)/2.
6
1, 1, 1, 2, 2, 1, 2, 3, 3, 4, 3, 6, 5, 3, 2, 3, 5, 6, 5, 7, 7, 8, 8, 9, 7, 8, 6, 10, 11, 4, 4, 8, 9, 8, 5, 8, 10, 12, 13, 18, 12, 16, 15, 20, 14, 12
OFFSET
1,4
LINKS
David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.]
KEYWORD
more,nonn
AUTHOR
Omar E. Pol, Feb 06 2010
EXTENSIONS
a(16)-a(46) from Robert Price, Jun 17 2019
STATUS
approved