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%I #14 Mar 18 2020 00:03:40
%S 32,64,81,121,125,128,169,243,256,289,320,343,361,375,384,405,448,486,
%T 512,529,567,625,640,686,729,768,841,875,896,961,1024,1029,1215,1250,
%U 1280,1331,1369,1458,1536,1681,1701,1715,1792,1849,1875,2048,2187,2197,2209,2401,2430,2500,2560,2592,2656,2662,2738,2744,2752,2809,2816,2848,2916,2944,3008,3072,3104,3125,3136,3200,3328,3362,3375,3392,3402,3430,3456,3481,3483,3584,3645,3698,3712
%N Numbers n such that A080670(n) < n.
%H Alois P. Heinz, <a href="/A195330/b195330.txt">Table of n, a(n) for n = 1..10000</a> (first 220 terms from Robert Price)
%p b:= proc(n) option remember; `if`(n=1, 1, (l->
%p parse(cat(seq(`if`(l[i, 2]=1, l[i, 1], [l[i, 1],
%p l[i, 2]][]), i=1..nops(l)))))(sort(ifactors(n)[2])))
%p end:
%p a:= proc(n) option remember; local k; for k from
%p `if`(n=1, 0, a(n-1))+1 while b(k)>=k do od; k
%p end:
%p seq(a(n), n=1..100); # _Alois P. Heinz_, Mar 17 2020
%t A080670 = Cases[Import["https://oeis.org/A080670/b080670.txt", "Table"], {_, _}][[All, 2]];
%t Select[Range[3712], A080670[[#]] < # &] (* _Robert Price_, Mar 17 2020 *)
%o (PARI) is(n,f=factor(n))=eval(concat(vector(#f~,i,if(f[i,2]==1, Str(f[i,1]), Str(f[i,1],f[i,2])))))<n \\ _Charles R Greathouse IV_, Mar 18 2020
%Y Cf. A080670, A195331, A194263.
%K nonn,base
%O 1,1
%A _N. J. A. Sloane_, Sep 15 2011
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