



0, 1, 1, 1, 1, 1, 1, 3, 1, 3, 2, 2, 4, 4, 4, 4, 6, 3, 3, 1, 5, 3, 5, 5, 5, 1, 1, 3, 5, 5, 1, 5, 5, 1, 3, 5, 7, 5, 5, 1, 3, 5, 7, 5, 5, 5, 1, 3, 3, 5, 9, 1, 5, 5, 5, 1, 1, 3, 5, 5, 3, 1, 1, 3, 5, 5, 3, 1, 1, 3, 5, 7, 3, 7, 1, 1, 5, 5, 4, 2, 4, 6, 4, 4, 4, 8, 8, 4, 8, 4, 0, 4, 0, 2, 4, 2, 4, 8, 4, 4, 6, 4
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OFFSET

1,8


COMMENTS

From Michael De Vlieger, May 04 2022: (Start)
Zeros in this sequence correspond to fixed points in A093714.
Sequence exhibits intervals where terms have same parity. Parity changes when a run of odd terms in A093714 with even run length occurs. These runs begin with A093714(A351498(k)). Conjecture: the last parity change begins with a(1036044) = 9. (End)
Rival conjecture: The parity changes infinitely often. This would imply that A352932 contains infinitely many terms.  N. J. A. Sloane, May 04 2022


LINKS

N. J. A. Sloane, Table of n, a(n) for n = 1..10000
Michael De Vlieger, Scatterplot of a(n), n = 1..2^20, logarithmic along the xaxis, showing even terms in red and odd in blue, accentuating zeros that are confined to eventerm intervals, annotating positive and negative records, and labeling the last term a(k) in parity intervals, with k in A351498.


MATHEMATICA

nn = 120; c = {1}; s = 0; a[1] = j = 1; u = 2; Do[k = u; While[Nand[FreeQ[c, k], CoprimeQ[j, k], k != j + 1], k++]; j = k; AppendTo[c, k]; a[i] = k  i; If[k == u, While[MemberQ[c, u], u++]; c = DeleteCases[c, _?(# < u &)]], {i, 2, nn}], Array[a, nn] (* Michael De Vlieger, May 04 2022 *)


CROSSREFS

Cf. A093714, A351498, A352932.
Sequence in context: A355784 A213885 A347739 * A083208 A126682 A016571
Adjacent sequences: A352928 A352929 A352930 * A352932 A352933 A352934


KEYWORD

sign


AUTHOR

N. J. A. Sloane, May 04 2022


STATUS

approved



