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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.

A106456 Natural numbers mapped to Dyck path encodings of the rooted plane trees obtained by recursing on the exponents of the GF(2)[X] factorization of n.

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%I A106456 #10 Jul 11 2015 10:24:15
%S A106456 0,10,1010,1100,110010,101100,101010,110100,10110010,11001100,
%T A106456 10101010,10110100,1010101010,10101100,11010010,111000,11100010,
%U A106456 1011001100,101010101010,1100110100,11001010,1010101100,101010110010
%N A106456 Natural numbers mapped to Dyck path encodings of the rooted plane trees obtained by recursing on the exponents of the GF(2)[X] factorization of n.
%C A106456 Note that we recurse on the exponent + 1 for all other irreducible polynomials except the largest one in the GF(2)[X] factorization. Thus for 6 = A048723(3,1) X A048723(2,1) we construct a tree by joining trees 1 and 2 with a new root node, for 7 = A048723(7,1) X A048723(3,0) X A048723(2,0) we join three 1-trees (single leaves) with a new root node, for 8 = A048273(2,3) we add a single edge below tree 3 and for 9 = A048723(7,1) X A048723(3,1) X A048273(2,0) we connect the trees 1 and 2 and 1 with a new root node.
%H A106456 A. Karttunen, <a href="/A091247/a091247.scm.txt">Scheme-program for computing this sequence.</a>
%e A106456 The rooted plane trees encoded here are:
%e A106456 .....................o....o..........o.........o...o....o.....
%e A106456 .....................|....|..........|..........\./.....|.....
%e A106456 .......o....o...o....o....o...o..o...o..o.o.o....o....o.o.o...
%e A106456 .......|.....\./.....|.....\./....\./....\|/.....|.....\|/....
%e A106456 *......*......*......*......*......*......*......*......*.....
%e A106456 1......2......3......4......5......6......7......8......9.....
%Y A106456 a(n) = A007088(A106455(n)) = A075166(A106443(n)). GF(2)[X]-analog of A075166. Permutation of A063171. Same sequence shown in decimal: A106455. The digital length of each term / 2 (the number of o-nodes in the corresponding trees) is given by A106457. Cf. A106451-A106454.
%K A106456 nonn,base
%O A106456 1,2
%A A106456 _Antti Karttunen_, May 09 2005