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LCM of n and largest integer <= sqrt(n).
2

%I #20 Apr 27 2017 19:34:54

%S 1,2,3,4,10,6,14,8,9,30,33,12,39,42,15,16,68,36,76,20,84,44,92,24,25,

%T 130,135,140,145,30,155,160,165,170,35,36,222,114,78,120,246,42,258,

%U 132,90,138,282,48,49,350,357,364,371,378,385,56,399,406,413,420

%N LCM of n and largest integer <= sqrt(n).

%C a(n) = n iff n is in A006446. - _Ivan Neretin_, Apr 27 2017

%H Ivan Neretin, <a href="/A241083/b241083.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = lcm(n, floor(sqrt(n))) = lcm(n, A000196(n)). - _Wesley Ivan Hurt_, Apr 15 2014

%e a(18) cannot be 18 because 18 is not a multiple of 4, the largest integer <= sqrt(18).

%p A241083:= n-> ilcm(n,floor(sqrt(n))): seq(A241083(n), n=1..50); # _Wesley Ivan Hurt_, Apr 15 2014

%t Table[LCM[n, Floor[Sqrt[n]]], {n, 50}] (* _Wesley Ivan Hurt_, Apr 15 2014 *)

%Y A179204 is a sequence that can be defined in terms of this sequence.

%Y Cf. A000196.

%K nonn,look,easy

%O 1,2

%A _J. Lowell_, Apr 15 2014

%E Extended by _Wesley Ivan Hurt_, Apr 15 2014