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 A225855 Difference between the number of nonnegative evil and odious multiples of n less than 2^n. 1
 -1, -1, 3, -1, 5, 9, -7, -1, 27, 25, 11, 162, 13, 49, 521, -1, 697, 2196, 19, 625, 8435, 121, -23, 59049, 3120, 169, 177147, 2401, 29, 982635 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS It appears that for n = 2^i*p, i>0, p prime, a(n) = p^(2^i) or a multiple of it. For which n is a(n) negative? For prime n and related conjectures, see A133954. LINKS PROG (PARI) a(n)=sum(i=0, floor(2^n/n), subst(Pol(binary(i*n)), x, 1)%2==0)-sum(i=0, floor(2^n/n), subst(Pol(binary(i*n)), x, 1)%2) CROSSREFS Cf. A000069, A001969, Sequence in context: A029723 A187370 A215456 * A201751 A202504 A055199 Adjacent sequences:  A225852 A225853 A225854 * A225856 A225857 A225858 KEYWORD sign,hard,more AUTHOR Ralf Stephan, Aug 31 2013 STATUS approved

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Last modified February 23 14:35 EST 2020. Contains 332163 sequences. (Running on oeis4.)