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Numbers k whose largest divisor <= sqrt(k) equals 10.
19

%I #13 May 19 2019 15:24:04

%S 100,110,120,130,140,150,160,170,190,200,230,250,290,310,370,410,430,

%T 470,530,590,610,670,710,730,790,830,890,970,1010,1030,1070,1090,1130,

%U 1270,1310,1370,1390,1490,1510,1570,1630,1670,1730,1790,1810,1910,1930

%N Numbers k whose largest divisor <= sqrt(k) equals 10.

%C See A161344 for more information.

%H Robert Israel, <a href="/A162530/b162530.txt">Table of n, a(n) for n = 1..10000</a>

%F Numbers k such that A033676(k) = 10.

%p filter:= n -> andmap(t -> t<=10 or t^2 > n, numtheory:-divisors(n)):

%p select(filter, [seq(n,n=100..10000,10)]); # _Robert Israel_, Aug 16 2018

%t ld10Q[n_]:=Last[Select[Divisors[n],#<=Sqrt[n]&]]==10; Select[Range[2000],ld10Q] (* _Harvey P. Dale_, Jan 30 2011 *)

%Y Cf. A033676, A008578, A161344, A161345, A161424, A161835, A162526, A162527, A162528, A162529, A162531, A162532.

%K easy,nonn

%O 1,1

%A _Omar E. Pol_, Jul 05 2009

%E More terms from _Gerard P. Michon_, Jul 12 2009