

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
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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

Table of n, a(n) for n=1..30.


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



