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Numbers k whose largest divisor <= sqrt(k) equals 6.
17

%I #10 Feb 27 2019 02:50:48

%S 36,42,48,54,60,66,78,102,114,138,174,186,222,246,258,282,318,354,366,

%T 402,426,438,474,498,534,582,606,618,642,654,678,762,786,822,834,894,

%U 906,942,978,1002,1038,1074,1086,1146,1158,1182,1194,1266,1338,1362

%N Numbers k whose largest divisor <= sqrt(k) equals 6.

%C See A161344 for more information.

%F Numbers k such that A033676(k)=6.

%p A033676 := proc(n) local dvs; dvs := sort(convert(numtheory[divisors](n),list)) ; op(floor((nops(dvs)+1)/2) ,dvs) ; end: for n from 1 to 2000 do if A033676(n) = 6 then printf("%d,",n) ; fi; od: # _R. J. Mathar_, Jul 13 2009

%t ld6Q[n_]:=Last[Select[Divisors[n],#<=Sqrt[n]&]]==6; Select[Range[ 1400],ld6Q] (* _Harvey P. Dale_, Mar 08 2012 *)

%Y Cf. A033676, A008578, A161344, A161345, A161424, A161835, A162527, A162528, A162529, A162530, A162531, A162532.

%K easy,nonn

%O 1,1

%A _Omar E. Pol_, Jul 05 2009

%E More terms from _R. J. Mathar_, Jul 13 2009