cp's OEIS Frontend

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.

A288775 Difference between the total number of toothpicks in the toothpick structure of A139250 that are parallel to the initial toothpick after n odd stages, and the total number of "ON" cells at n-th stage in the "Ulam-Warburton" two-dimensional cellular automaton of A147562.

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%I A288775 #32 Jul 07 2017 08:11:48
%S A288775 0,0,0,0,0,0,4,0,0,0,4,0,4,4,28,0,0,0,4,0,4,4,28,0,4,4,28,4,28,32,132,
%T A288775 0,0,0,4,0,4,4,28,0,4,4,28,4,28,32,132,0,4,4,28,4,28,32,132,4,28,32,
%U A288775 132,32,136,176,524,0,0,0,4,0,4,4,28,0,4,4,28,4,28,32,132,0,4,4,28,4,28,32,132,4,28,32
%N A288775 Difference between the total number of toothpicks in the toothpick structure of A139250 that are parallel to the initial toothpick after n odd stages, and the total number of "ON" cells at n-th stage in the "Ulam-Warburton" two-dimensional cellular automaton of A147562.
%C A288775 It appears that a(n) = 0 if and only if n is a member of A048645.
%C A288775 First differs from A255263 at a(14), with which it shares infinitely many terms.
%C A288775 It appears that A147562(n) = A162795(n) = A169707(n) = A255366(n) = A256250(n) = A256260(n), if n is a member of A048645.
%H A288775 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>
%H A288775 <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%F A288775 a(n) = A162795(n) - A147562(n).
%e A288775 Written as an irregular triangle T(j,k), k>=1, in which the row lengths are the terms of A011782, the sequence begins:
%e A288775 0;
%e A288775 0;
%e A288775 0,0;
%e A288775 0,0,4,0;
%e A288775 0,0,4,0,4,4,28,0;
%e A288775 0,0,4,0,4,4,28,0,4,4,28,4,28,32,132,0;
%e A288775 0,0,4,0,4,4,28,0,4,4,28,4,28,32,132,0,4,4,28,4,28,32,132,4,28,32,132,32,136,176,524,0;
%e A288775 ...
%e A288775 It appears that if k is a power of 2 then T(j,k) = 0.
%e A288775 It appears that every column lists the same terms as its initial term.
%Y A288775 Cf. A011782, A048645, A139250, A139251, A147562, A147582, A162793, A162795, A169707, A255263, A255366, A256250, A256260.
%K A288775 nonn,tabf
%O A288775 1,7
%A A288775 _Omar E. Pol_, Jul 04 2017