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%I #19 Mar 27 2020 13:05:34
%S 2,10,105,1155,36465,969969,37182145,1078282205,39896441585,
%T 2668861960765,183330286997165,14415008697720995,775932344695001065,
%U 45780008337005062835,3909612711980232366109,261944051702675568529303,18598027670889965365580513
%N Smallest deficient number with n distinct prime factors.
%C From _Donovan Johnson_, Jan 25 2009: (Start)
%C a(14) <= 45780008337005062835;
%C a(15) <= 3909612711980232366109;
%C a(16) <= 261944051702675568529303. (End)
%F a(n) = Min{x; sigma(x)/2x < 1 and A001221(x) = n}.
%e For n=5: a(5) = 36465 = 3*5*11*13*17; sigma(36465) = 72576 < 72930 = 2*sigma(a(5)).
%t q[x_] := Apply[Times, Table[Prime[w], {w, 1, x}]]; q[0]=1; Do[s=DivisorSigma[1, n]; If[Greater[2*n, s]&&Equal[lf[n], j]&& Equal[fl, 1], Print[{n, {s, 2*n}, j}]; fl=0], {n, q[j], q[j+2]}], {j, 1, 6}]
%Y Cf. A000203, A002110, A005100.
%K nonn
%O 1,1
%A _Labos Elemer_, Sep 01 2003
%E a(6) corrected and a(7)-a(13) from _Donovan Johnson_, Jan 25 2009
%E a(14)-a(17) from _Jon E. Schoenfield_, Jul 08 2018
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