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%I #17 Feb 20 2021 23:13:10
%S 0,1,1,1,1,1,1,0,1,1,1,0,1,1,1,0,1,0,1,1,1,1,1,0,1,1,0,1,1,0,1,0,1,1,
%T 1,0,1,1,1,0,1,1,1,1,0,1,1,0,1,0,1,1,1,0,1,0,1,1,1,0,1,1,0,0,1,1,1,1,
%U 1,0,1,0,1,1,0,1,1,1,1,0,0,1,1,0,1,1,1
%N Number of superior prime divisors of n.
%C We define a divisor d|n to be superior if d >= n/d. Superior divisors are counted by A038548 and listed by A161908.
%C All terms are binary numbers.
%e The sequence of sets of superior prime divisors of each positive integer begins: {}, {2}, {3}, {2}, {5}, {3}, {7}, {}, {3}, {5}, {11}, {}, {13}, {7}, {5}, {}, {17}, {}, {19}, {5}, ...
%t Table[Length[Select[Divisors[n],PrimeQ[#]&&#>=n/#&]],{n,100}]
%Y Positions of ones are A063538.
%Y Positions of zeros are A063539.
%Y The inferior version is A063962.
%Y The strictly inferior version is A333806.
%Y The version for squarefree instead of prime divisors is A341592.
%Y The version for prime power instead of prime divisors is A341593.
%Y Dominates A341642 (the strictly superior version).
%Y The version for odd instead of prime divisors is A341675.
%Y The unique superior prime divisors of the positive positions are A341676.
%Y A001221 counts prime divisors, with sum A001414.
%Y A033677 selects the smallest superior divisor.
%Y A038548 counts superior (or inferior) divisors.
%Y A056924 counts strictly superior (or strictly inferior) divisors.
%Y A161908 lists superior divisors.
%Y A207375 list central divisors.
%Y - Inferior: A033676, A066839, A069288, A161906, A217581, A333749, A333750.
%Y - Superior: A051283, A059172, A070038, A072500, A116882, A116883.
%Y - Strictly Inferior: A060775, A333805, A341596, A341674.
%Y - Strictly Superior: A048098, A064052 A140271, A238535, A341594, A341595, A341644, A341645, A341646, A341673.
%Y Cf. A000005, A000203, A001222, A001248, A006530, A020639, A112798, A341643.
%K nonn
%O 1
%A _Gus Wiseman_, Feb 19 2021
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