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%I A145377 #18 May 09 2018 16:42:48
%S A145377 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,
%T A145377 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,
%U A145377 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
%N A145377 a(n) = A002324(n) mod 2.
%H A145377 Antti Karttunen, <a href="/A145377/b145377.txt">Table of n, a(n) for n = 1..65537</a>
%H A145377 J. S. Rutherford, <a href="http://dx.doi.org/10.1007/BF01164477">Generating functions for the cage isomers of the C_{20n} icosahedral fullerenes, J. Mathematical Chem.</a>, 14 (1993), 385-390. See Eq. (3).
%H A145377 J. S. Rutherford, <a href="https://dx.doi.org/10.1107/S0108767392000898">The enumeration and symmetry-significant properties of derivative lattices</a>, Act. Cryst. A48 (1992), 500-508. [See Sect. (7), p. 505.]
%H A145377 <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F A145377 a(n) = A195198(n) for n >= 1.
%F A145377 a(n) = Sum_{ m: m^2|n } A154272(n/m^2). - _Andrey Zabolotskiy_, May 07 2018
%t A145377 Array[Boole@ OddQ@ If[# < 1, 0, DivisorSum[#, KroneckerSymbol[-3, #] &]] &, 105] (* _Michael De Vlieger_, Nov 05 2017, after _Michael Somos_ at A002324 *)
%o A145377 (PARI)
%o A145377 A002324(n) = if( n<1, 0, sumdiv(n, d, (d%3==1) - (d%3==2)));
%o A145377 A145377(n) = (A002324(n)%2); \\ _Antti Karttunen_, Nov 06 2017
%Y A145377 Essentially same as A195198.
%Y A145377 Cf. A002324, A154272, A003050.
%K A145377 nonn,mult
%O A145377 1,1
%A A145377 _N. J. A. Sloane_, Mar 12 2009
%E A145377 More terms from _Antti Karttunen_, Nov 05 2017

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