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A318886 The sum of absolute values of the coefficients in the n-th cyclotomic polynomial minus the largest prime factor of n; a(1)=1 by convention.

%I A318886 #9 Sep 12 2018 10:50:07
%S A318886 1,0,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,2,0,0,0,0,0,0,0,0,2,0,0,4,0,
%T A318886 10,0,0,0,4,0,0,2,0,0,2,0,0,0,0,0,6,0,0,0,6,0,6,0,0,2,0,0,2,0,18,4,0,
%U A318886 0,8,10,0,0,0,0,2,0,20,4,0,0,0,0,0,2,24,0,10,0,0,2,10,0,10,0,12,0,0,0,4,0,0,6,0,0,28
%N A318886 The sum of absolute values of the coefficients in the n-th cyclotomic polynomial minus the largest prime factor of n; a(1)=1 by convention.
%C A318886 See comments in A070536.
%H A318886 Antti Karttunen, <a href="/A318886/b318886.txt">Table of n, a(n) for n = 1..65537</a>
%t A318886 Array[Total@ Abs@ CoefficientList[Cyclotomic[#, x], x] - FactorInteger[#][[-1, 1]] &, 105] (* _Michael De Vlieger_, Sep 10 2018 *)
%o A318886 (PARI)
%o A318886 A006530(n) = if(n>1, vecmax(factor(n)[, 1]), 1); \\ From A006530.
%o A318886 A318884(n) = vecsum(apply(abs,Vec(polcyclo(n))));
%o A318886 A318886(n) = (A318884(n) - A006530(n));
%Y A318886 Cf. A006530, A318884.
%Y A318886 Differs from A070536 for the first time at n=105, where a(105) = 28, while A070536(105) = 26.
%K A318886 nonn
%O A318886 1,15
%A A318886 _Antti Karttunen_, Sep 10 2018