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%I #7 Feb 24 2021 02:48:19
%S 2,4,7,10,13,17,23,28,31,35,41,47,53,61,73,82,85,89,95,101,107,115,
%T 127,137,143,151,163,175,187,203,227,244,247,251,257,263,269,277,289,
%U 299,305,313,325,337,349,365,389,407,413,421,433,445,457,473,497,517,529,545,569,593,617,649,697,730,733,737,743,749,755,763,775,785,791,799,811,823,835
%N a(n) = A173522(n)/2.
%H David Applegate, Omar E. Pol and N. J. A. Sloane, <a href="/A000695/a000695_1.pdf">The Toothpick Sequence and Other Sequences from Cellular Automata</a>, 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.]
%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>
%t f[n_] := f[n] = Sum[Binomial[1, n - k] Mod[ Binomial[k, j], 2], {k, 0, n}, {j, 0, k}]; g[n_] := Sum[f@k, {k, 0, n}]; Array[g, 77]/2
%Y Cf. A105321, A139250, A173522.
%K nonn
%O 2,1
%A _Omar E. Pol_, May 29 2010
%E I changed the title (its index), the offset, extended the sequence and added the Mathematica coding _Robert G. Wilson v_, Jun 28 2010
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