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A173522
Zero together with the partial sums of A105321.
5
0, 1, 4, 8, 14, 20, 26, 34, 46, 56, 62, 70, 82, 94, 106, 122, 146, 164, 170, 178, 190, 202, 214, 230, 254, 274, 286, 302, 326, 350, 374, 406, 454, 488, 494, 502, 514, 526, 538, 554, 578, 598, 610, 626, 650, 674, 698, 730, 778, 814, 826, 842, 866, 890, 914, 946
OFFSET
0,3
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.]
T. Pisanski and T. W. Tucker, Growth in Repeated Truncations of Maps, Preprint series, Univ. of Ljubljana, Vol. 38 (2000), 696.
MATHEMATICA
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, 55, 0] (* Robert G. Wilson v, Jun 28 2010 *)
PROG
(PARI) f(n) = sum(k=0, n, binomial(1, n-k)*sum(j=0, k, binomial(k, j) % 2));
a(n) = if (n==0, 0, sum(k=0, n-1, f(k))); \\ or
lista(nn) = {print1(s=0, ", "); for (n=0, nn-1, s += f(n); print1(s, ", "); ); } \\ Michel Marcus, Apr 29 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, May 29 2010
EXTENSIONS
More terms from Robert G. Wilson v, Jun 28 2010
STATUS
approved