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%I #18 Jul 18 2023 13:03:06
%S 1,2,6,12,12,24,72,72,144,144,144,432,864,864,864,864,1728,1728,5184,
%T 5184,5184,10368,10368,10368,10368,10368,31104,62208,62208,62208,
%U 62208,62208,62208,124416,124416,124416,373248,373248,373248,373248,746496
%N Least common multiple of first n 3-smooth numbers.
%C Subsequence of A003586.
%H Amiram Eldar, <a href="/A096075/b096075.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Lc#lcm">Index entries for sequences related to lcm's</a>.
%F a(n) > a(n-1) iff A003586(n) is a power of 2 or of 3 (cf. A006899, A022330, A022331).
%e The first seven 3-smooth numbers are {1, 2, 3, 4, 6, 8, 9} and their lcm is 72. - _David A. Corneth_, Jul 13 2023
%t seq[max_] := Module[{sm3 = Sort[Flatten[Table[2^i*3^j, {i, 0, Log2[max]}, {j, 0, Log[3, max/2^i]}]]], e2, e3}, e2 = FoldList[Max, IntegerExponent[sm3, 2]]; e3 = FoldList[Max, IntegerExponent[sm3, 3]]; 2^e2*3^e3]; seq[1000] (* _Amiram Eldar_, Jul 13 2023 *)
%Y Cf. A003418, A003586, A006899, A022330, A022331, A051451.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Jul 21 2004
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