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A145377
a(n) = A002324(n) mod 2.
5
1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
1,1
FORMULA
a(n) = A195198(n) for n >= 1.
a(n) = Sum_{ m: m^2|n } A154272(n/m^2). - Andrey Zabolotskiy, May 07 2018
MATHEMATICA
Array[Boole@ OddQ@ If[# < 1, 0, DivisorSum[#, KroneckerSymbol[-3, #] &]] &, 105] (* Michael De Vlieger, Nov 05 2017, after Michael Somos at A002324 *)
PROG
(PARI)
A002324(n) = if( n<1, 0, sumdiv(n, d, (d%3==1) - (d%3==2)));
A145377(n) = (A002324(n)%2); \\ Antti Karttunen, Nov 06 2017
CROSSREFS
Essentially same as A195198.
Sequence in context: A266326 A185295 A214295 * A374113 A374107 A373585
KEYWORD
nonn,mult
AUTHOR
N. J. A. Sloane, Mar 12 2009
EXTENSIONS
More terms from Antti Karttunen, Nov 05 2017
STATUS
approved