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A347312
Parity of A347113.
2
1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1
OFFSET
1
COMMENTS
Terms k = A347113(n) conspicuously greater than n are even, though most even k are less than n. Given 2^19 terms of A347113, 45620 even terms exceed n, while 237855 are less than n, and 19 fixed points are even. Odd k are largely less than n; for 2^19 terms of A347113, there are 12 odd terms that exceed n, e.g., A347113(85) = 87, and 1 odd fixed point A347113(1) = 1. - Michael De Vlieger, Nov 16 2021
LINKS
Michael De Vlieger, Log-log scatterplot of A347113(n), n=1..2^19, indicating parity, even terms in blue, odds in red.
MATHEMATICA
c[_] = 0; j = m = 2; {1}~Join~Reap[Do[If[IntegerQ@ Log2[i], While[c[m] > 0, m++]]; Set[k, m]; While[Or[c[k] > 0, k == j, GCD[j, k] == 1], k++]; Sow[Boole@ OddQ@ k]; Set[c[k], i]; j = k + 1, {i, 105}]][[-1, -1]] (* Michael De Vlieger, Nov 16 2021 *)
CROSSREFS
Cf. A347113.
Sequence in context: A319691 A079979 A288711 * A089010 A162289 A373139
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Sep 06 2021
STATUS
approved