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%I #10 Dec 15 2017 17:36:02
%S 0,0,0,0,1,0,2,1,1,2,2,1,3,2,1,1,3,3,2,1,2,3,4,1,4,2,4,3,2,1,4,3,4,2,
%T 4,1,3,4,3,3,3,4,3,2,5,4,4,2,5,5,2,5,5,2,4,2,4,4,4,5,3,3,6,1,4,4,6,6,
%U 2,4,4,5,5,4,2,4,7,4,2,4,5,5,6,3,5,4,5,4,2,3,4
%N Number of distinct differences between consecutive anti-divisors of n (ordered by size).
%C See A066272 for definition of anti-divisor.
%e For n=17, anti-divisors={2,3,5,7,11}; differences={1,2,2,4}; a(17) = number of distinct differences = 3.
%p read("transforms");
%p A074746 := proc(n)
%p local advs ;
%p advs := sort(convert(antidivisors(n),list)) ;
%p nops(convert(DIFF(advs),set)) ;
%p end proc: # _R. J. Mathar_, Oct 01 2011
%Y Cf. A066272.
%K easy,nonn
%O 1,7
%A _Jason Earls_, Sep 06 2002