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 A337925 Digits of n rearranged to be the smallest number with the fewest possible prime factors, counted with multiplicity. Terms retain the same number of digits as n, i.e. leading digits may not be zero. 1
 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 21, 13, 41, 15, 61, 17, 18, 19, 20, 21, 22, 23, 42, 25, 26, 27, 82, 29, 30, 13, 23, 33, 43, 53, 63, 37, 83, 39, 40, 41, 42, 43, 44, 45, 46, 47, 84, 49, 50, 15, 25, 53, 45, 55, 65, 57, 58, 59, 60, 61, 26, 63, 46, 65, 66, 67, 86, 69, 70, 17, 27, 37, 47, 57, 67, 77 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Rémy Sigrist, Table of n, a(n) for n = 1..10000 FORMULA a(a(n)) = a(n). - Rémy Sigrist, Oct 22 2020 MATHEMATICA a[n_] := Module[{p = FromDigits /@ Select[Permutations @ IntegerDigits[n], First[#] > 0 &]}, o = PrimeOmega[p]; Min[p[[Position[o, Min[o]] // Flatten]]]]; Array[a, 100] (* Amiram Eldar, Oct 19 2020 *) PROG (PARI) a(n) = {my(d = digits(n), v = select(x->#(digits(x))==#d, vector((#d)!, i, fromdigits(vector(#d, k, d[numtoperm(#d, i-1)[k]])))), b = vecmin(vector(#v, k, bigomega(v[k])))); vecmin(select(x->(bigomega(x)==b), v)); } \\ Michel Marcus, Oct 19 2020 CROSSREFS Cf. A001222, A004186, A328447. Sequence in context: A188650 A132578 A101318 * A130575 A330760 A064222 Adjacent sequences: A337922 A337923 A337924 * A337926 A337927 A337928 KEYWORD nonn,look,base AUTHOR Roderick Kimball, Sep 30 2020 STATUS approved

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Last modified December 7 04:15 EST 2023. Contains 367629 sequences. (Running on oeis4.)