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A051548 a(n) = LCM { tau(1), ..., tau(n) }.

%I A051548 #17 Dec 11 2024 08:42:37
%S A051548 1,1,2,2,6,6,12,12,12,12,12,12,12,12,12,12,60,60,60,60,60,60,60,60,
%T A051548 120,120,120,120,120,120,120,120,120,120,120,120,360,360,360,360,360,
%U A051548 360,360,360,360,360,360,360,360,360,360,360,360,360,360,360
%N A051548 a(n) = LCM { tau(1), ..., tau(n) }.
%C A051548 From _Antti Karttunen_, Aug 23 2017: (Start)
%C A051548 a(0) = 1 as an empty product.
%C A051548 Records (new values) occur at positions: 0, 2, 4, 6, 24, 36, 64, 120, 840, 900, 1024, 1296, 4096, 7560, ...
%C A051548 (End)
%H A051548 Antti Karttunen, <a href="/A051548/b051548.txt">Table of n, a(n) for n = 0..4096</a>
%H A051548 <a href="/index/Lc#lcm">Index entries for sequences related to lcm's</a>
%p A051548 a:= proc(n) option remember; `if`(n=0, 1,
%p A051548        ilcm(a(n-1), numtheory[tau](n)))
%p A051548     end:
%p A051548 seq(a(n), n=0..55);  # _Alois P. Heinz_, Dec 11 2024
%t A051548 Block[{nn = 60, s}, s = DivisorSigma[0, Range@ nn]; {1}~Join~Table[LCM @@ s[[1 ;; n]], {n, nn}]] (* _Michael De Vlieger_, Aug 23 2017 *)
%o A051548 (Scheme, with memoization-macro definec) (definec (A051548 n) (if (<= n 1) 1 (lcm (A000005 n) (A051548 (- n 1))))) ;; _Antti Karttunen_, Aug 23 2017
%Y A051548 Cf. A000005.
%K A051548 nonn
%O A051548 0,3
%A A051548 _N. J. A. Sloane_
%E A051548 a(0) = 1 inserted by _Antti Karttunen_, Aug 23 2017