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 A132138 Characteristic function of the set of numbers defined in A002977. 4

%I

%S 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,

%T 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,

%U 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

%N Characteristic function of the set of numbers defined in A002977.

%C a(A002977(n)) = 1 and a(A132142(n)) = 0.

%H R. Zumkeller, <a href="/A132138/b132138.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>

%F 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)).

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Aug 20 2007

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Last modified December 15 15:10 EST 2019. Contains 329999 sequences. (Running on oeis4.)