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A111159 Numbers n such that A111075(n) is odd. 1
1, 3, 4, 6, 12, 16, 24, 25, 27, 48, 49, 54, 64, 75, 96, 100, 108, 121, 147, 150, 169, 192, 196, 216, 243, 256, 289, 294, 300, 361, 363, 384, 400, 432, 484, 486, 507, 529, 588, 600, 625, 675, 676, 726, 768, 784, 841, 864, 867, 961, 972, 1014, 1024 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..53.

FORMULA

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."

It is not difficult to show that the conjecture is true. - Max Alekseyev, Oct 12 2005

CROSSREFS

Sequence in context: A044843 A293593 A024373 * A210523 A109069 A329953

Adjacent sequences:  A111156 A111157 A111158 * A111160 A111161 A111162

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Oct 12 2005

STATUS

approved

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Last modified December 14 19:27 EST 2019. Contains 329987 sequences. (Running on oeis4.)