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A151707
a(0)=1, a(1)=1; a(2^i+j) = 2*a(j) + 2*a(j+1) for 0 <= j < 2^i.
16
1, 1, 4, 10, 4, 10, 28, 28, 4, 10, 28, 28, 28, 76, 112, 64, 4, 10, 28, 28, 28, 76, 112, 64, 28, 76, 112, 112, 208, 376, 352, 136, 4, 10, 28, 28, 28, 76, 112, 64, 28, 76, 112, 112, 208, 376, 352, 136, 28, 76, 112, 112, 208, 376, 352, 184, 208, 376, 448, 640, 1168, 1456, 976, 280
OFFSET
0,3
COMMENTS
Equals A151705 + A151706.
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.]
MAPLE
See A151702 for Maple code.
MATHEMATICA
a = {1, 1}; Do[AppendTo[a, 2 a[[j]] + 2 a[[j + 1]]], {i, 6}, {j, 2^i}]; a (* Ivan Neretin, Jul 04 2017 *)
CROSSREFS
For the recurrence a(2^i+j) = C*a(j) + D*a(j+1), a(0) = A, a(1) = B for following values of (A B C D) see: (0 1 1 1) A118977, (1 0 1 1) A151702, (1 1 1 1) A151570, (1 2 1 1) A151571, (0 1 1 2) A151572, (1 0 1 2) A151703, (1 1 1 2) A151573, (1 2 1 2) A151574, (0 1 2 1) A160552, (1 0 2 1) A151704, (1 1 2 1) A151568, (1 2 2 1) A151569, (0 1 2 2) A151705, (1 0 2 2) A151706, (1 1 2 2) A151707, (1 2 2 2) A151708.
Sequence in context: A121512 A291527 A010715 * A059132 A059136 A128505
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jun 06 2009
STATUS
approved