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%I #13 Mar 12 2015 22:37:15
%S 5,10,18,32,45,94,220,175,325,247,630,578,637,1012,2712,3867,4851,
%T 2993,10230,2363,6435
%N Smallest k such that n is the n-th largest anti-divisor of k.
%e a(7) = 94 because the sorted anti-divisors of 94 are (63, 38, 27, 21, 10, 9, 7, 3, 2) and 7 is the 7th anti-divisor.
%p antidivisors := proc(n)
%p local a, k;
%p a := {} ;
%p for k from 2 to n-1 do
%p if abs((n mod k)- k/2) < 1 then
%p a := a union {k} ;
%p end if;
%p end do:
%p convert(a,list) ;
%p end proc:
%p A226445 := proc(n)
%p local k,adv;
%p for k from 3 do
%p adv := sort(antidivisors(k)) ;
%p if nops(adv) >= n then
%p if op(-n,adv) = n then
%p return k;
%p end if;
%p end if;
%p end do:
%p end proc: # _R. J. Mathar_, Jun 18 2013
%Y Cf. A066272, A130799.
%K nonn,less
%O 2,1
%A _Juri-Stepan Gerasimov_, Jun 06 2013
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