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A330622
Lexicographically earliest sequence of nonnegative terms such that for any n > 0 and k > 0, a(n+2*k) <> gcd(a(n), a(n+k)).
3
0, 0, 1, 0, 0, 1, 2, 2, 3, 0, 0, 3, 0, 0, 4, 2, 5, 3, 5, 6, 3, 4, 4, 6, 6, 5, 4, 0, 0, 7, 0, 0, 7, 8, 8, 9, 0, 0, 7, 0, 0, 3, 8, 5, 3, 5, 9, 9, 5, 8, 7, 9, 2, 7, 10, 4, 3, 10, 6, 7, 6, 10, 10, 6, 6, 4, 10, 4, 9, 6, 11, 6, 6, 8, 11, 5, 8, 8, 4, 10, 11, 0, 0, 7
OFFSET
1,7
COMMENTS
This sequence differs radically from the variant where we consider only positive terms (A330623).
FORMULA
a(n) = 0 iff n belongs to A003278.
PROG
(C) See Links section.
CROSSREFS
Cf. A003278 (positions of 0's), A330623 (positive variant).
See A330267 for similar sequences.
Sequence in context: A246471 A289814 A328686 * A330629 A304760 A304759
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Dec 21 2019
STATUS
approved