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A379728
Absolute value of first differences of paperfolding sequence A014577.
1
0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0
OFFSET
1
LINKS
Jeffrey Shallit, Cloitre's Self-Generating Sequence, arXiv:2501.00784 [math.CO], 2025.
FORMULA
Generated by infinitely iterating the morphism a->ab, b->cd, c->ef, d->cd, e->ab, f->gh, g->ef, h->gh, starting with a, followed by mapping a,d,f,g to 0 and b,c,e,h to 1.
MATHEMATICA
Abs[Differences[(1 + JacobiSymbol[-1, Range[100]])/2]] (* Paolo Xausa, Jan 03 2025 *)
Abs[Differences[Array[Boole[BitAnd[#, BitAnd[#, -#]*2] == 0] &, 100]]] (* Paolo Xausa, Jan 03 2025, after Joerg Arndt C++ code in A014577 *)
CROSSREFS
Cf. A014577, A343173 (signed version), A157196 (run lengths).
Sequence in context: A100821 A139689 A204175 * A343173 A285255 A324823
KEYWORD
nonn
AUTHOR
Jeffrey Shallit, Dec 31 2024
STATUS
approved