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A132138
Characteristic function of the set of numbers defined in A002977.
4
1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
1,1
COMMENTS
a(A002977(n)) = 1 and a(A132142(n)) = 0.
FORMULA
a(n) = if chi(n) then 1 else 0, where chi(n) = if n<3 then (n=1) else ((n mod 2 = 1) AND chi((n-1)/2)) OR ((n mod 3 = 1) AND chi((n-1)/3)).
CROSSREFS
Sequence in context: A118174 A353815 A156258 * A141212 A341347 A137893
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 20 2007
STATUS
approved