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%I #12 May 21 2020 10:57:44
%S 1,-1,-5,-5,-21,11,-53,-53,-53,459,-565,-565,-4661,3531,19915,19915,
%T -45621,-45621,-307765,-307765,740811,2837963,-1356341,-1356341,
%U -1356341,32198091,32198091,32198091,-236237365,-773108277
%N Partial sums of A127511.
%H Alois P. Heinz, <a href="/A127513/b127513.txt">Table of n, a(n) for n = 1..1000</a>
%e a(3) = -5 = (1 - 2 - 4).
%p a:= proc(n) option remember;
%p numtheory[mobius](n)*2^(n-1) +`if`(n=1, 0, a(n-1))
%p end:
%p seq(a(n), n=1..30); # _Alois P. Heinz_, Apr 04 2012
%t Table[2^(n-1) MoebiusMu[n], {n, 1, 30}] // Accumulate (* _Jean-François Alcover_, May 21 2020 *)
%Y Cf. A127511, A127512.
%K sign
%O 1,3
%A _Gary W. Adamson_, Jan 17 2007
%E More terms from _R. J. Mathar_, Apr 04 2012