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%I #12 May 15 2018 08:38:26
%S 1,2,2,4,4,2,4,8,4,-2,16,8,8,0,8,16,32,16,32,16,32,0,64,32,-16,-64,
%T -160,-256,-128,-224,64,128,0,-256,256,-128,-128,-512,512,-256,512,0,
%U 512,0,-2048,-2816,-256,-1408,-1408,-2560,-2560,-4096,-1024,-1792,2048
%N A048106 is applied to A001405: the terms indicate whether more, equal or fewer unitary than non-unitary divisors of the central binomial coefficient exists.
%F A048106[ A001405[ x ] ] or A034444[ A001405[ x ] ] - A048105[ A001405[ x ] ] gives the terms resp.
%e n=54, binomial(54,27) has 3840 divisors of which 1024 are unitary and 2816 are not. The difference is -1792, so a(54) = -1792.
%o (PARI) a048106(n) = (2^(1+omega(n)) - numdiv(n));
%o a(n) = a048106(binomial(n, n\2)); \\ _Michel Marcus_, May 14 2018
%Y Cf. A001405, A048106.
%K sign
%O 1,2
%A _Labos Elemer_
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