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Numbers k whose largest divisor <= sqrt(k) equals 12.
19

%I #16 Jul 20 2024 12:34:07

%S 144,156,168,180,192,204,216,228,264,276,348,372,444,492,516,564,636,

%T 708,732,804,852,876,948,996,1068,1164,1212,1236,1284,1308,1356,1524,

%U 1572,1644,1668,1788,1812,1884,1956,2004,2076,2148,2172,2292,2316,2364

%N Numbers k whose largest divisor <= sqrt(k) equals 12.

%C See A161344 for more information.

%H Harvey P. Dale, <a href="/A162532/b162532.txt">Table of n, a(n) for n = 1..1000</a>

%F Numbers k such that A033676(k)=12.

%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 3500 do if A033676(n) = 12 then printf("%d,",n) ; fi; od: # _R. J. Mathar_, Jul 13 2009

%t ld12Q[n_]:=First[Select[Reverse[Divisors[n]],#<=Sqrt[n]&]]==12;Select[ 12*Range[ 200], ld12Q] (* _Harvey P. Dale_, Mar 29 2013 *)

%Y Cf. A033676, A008578, A161344, A161345, A161424, A161835, A162526, A162527, A162528, A162529, A162530, A162531.

%K easy,nonn

%O 1,1

%A _Omar E. Pol_, Jul 05 2009

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