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%I #9 Apr 12 2016 23:54:53
%S 0,2,3,6,6,7,8,13,9,12,13,13,15,18,10,22,15,17,16,22,14,26,14,22,19,
%T 30,13,30,17,20,20,35,18,30,20,27,27,33,18,34,27,26,20,45,16,28,26,34,
%U 26,36,21,47,21,28,26,46,20,32,24,32,32,42,16,52,23,33
%N Sum of numbers of divisors of positive numbers differing from n in one bit.
%C For all the positive numbers m obtained from n by flipping one bit of the binary representation of n, add the number of divisors A000005(m) of m.
%C Number of ordered pairs (a,b) of positive numbers such that a*b differs from n in exactly one binary digit, with no more binary digits than n.
%H Robert Israel, <a href="/A271716/b271716.txt">Table of n, a(n) for n = 1..10000</a>
%e For n = 5, flipping one bit yields (4, 7, 1), so a(5) = A000005(4) + A000005(7) + A000005(1) = 3 + 2 + 1 = 6.
%p f:= proc(x)
%p local m;
%p add(numtheory:-tau(m),m=[seq(Bits:-Xor(x,2^j),j=0..ilog2(x))])
%p end proc:
%p map(f, [$1..100]);
%Y Cf. A000005.
%K nonn
%O 1,2
%A _Robert Israel_, Apr 12 2016
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