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 A226445 Smallest k such that n is the n-th largest anti-divisor of k. 1
 5, 10, 18, 32, 45, 94, 220, 175, 325, 247, 630, 578, 637, 1012, 2712, 3867, 4851, 2993, 10230, 2363, 6435 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 LINKS EXAMPLE 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. MAPLE antidivisors := proc(n)     local a, k;     a := {} ;     for k from 2 to n-1 do         if abs((n mod k)- k/2) < 1 then             a := a union {k} ;         end if;     end do:     convert(a, list) ; end proc: A226445 := proc(n)     local k, adv;     for k from 3 do         adv := sort(antidivisors(k)) ;         if nops(adv) >= n then         if op(-n, adv) = n then             return k;         end if;         end if;     end do: end proc: # R. J. Mathar, Jun 18 2013 CROSSREFS Cf. A066272, A130799. Sequence in context: A025010 A299144 A058555 * A296552 A251928 A153370 Adjacent sequences:  A226442 A226443 A226444 * A226446 A226447 A226448 KEYWORD nonn,less AUTHOR Juri-Stepan Gerasimov, Jun 06 2013 STATUS approved

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Last modified June 21 03:24 EDT 2021. Contains 345354 sequences. (Running on oeis4.)