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A111159 Numbers n such that A111075(n) is odd. 1


%S 1,3,4,6,12,16,24,25,27,48,49,54,64,75,96,100,108,121,147,150,169,192,

%T 196,216,243,256,289,294,300,361,363,384,400,432,484,486,507,529,588,

%U 600,625,675,676,726,768,784,841,864,867,961,972,1014,1024

%N Numbers n such that A111075(n) is odd.

%F Conjecture: A111075(n) is odd whenever: (i) n = m^2 for all m>=1 such that 3 does not divide m, or (ii) n = 3*A028982(m) for all m>=1. Also, A028982 gives "Union of nonzero squares and twice squares."

%F It is not difficult to show that the conjecture is true. - _Max Alekseyev_, Oct 12 2005

%K nonn

%O 1,2

%A _Paul D. Hanna_, Oct 12 2005

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Last modified January 27 04:57 EST 2020. Contains 331291 sequences. (Running on oeis4.)