This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A153004 #10 Feb 24 2021 02:48:18
%S A153004 1,3,3,3,6,9,6,3,6,9,9,12,21,24,12,3,6,9,9,12,21,24,15,12,21,27,30,45,
%T A153004 66,60,24,3,6,9,9,12,21,24,15,12,21,27,30,45,66,60,27,12,21,27,30,45,
%U A153004 66,63,42,45,69,84,105,156,192,144,48,3
%N A153004 First differences of toothpick numbers A153003.
%H A153004 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 A153004 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>
%e A153004 Triangle begins:
%e A153004 1;
%e A153004 3,3;
%e A153004 3,6,9,6;
%e A153004 3,6,9,9,12,21,24,12;
%e A153004 3,6,9,9,12,21,24,15,12,21,27,30,45,66,60,24;
%t A153004 A139250[n_] := A139250[n] = Module[{m, k}, If[n == 0, Return[0]]; m = 2^(Length[IntegerDigits[n, 2]] - 1); k = (2 m^2 + 1)/3; If[n == m, k, k + 2 A139250[n - m] + A139250[n - m + 1] - 1]];
%t A153004 b[n_] := If[n == 0, 0, (3/4) (A139250[n + 1] - 3) + 1];
%t A153004 b /@ Range[0, 64] // Differences (* _Jean-François Alcover_, Apr 06 2020 *)
%Y A153004 Cf. A139251, A152968, A152978, A152998, A153000, A153003.
%Y A153004 Toothpick sequence: A139250.
%K A153004 nonn
%O A153004 1,2
%A A153004 _Omar E. Pol_, Jan 02 2009