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A051548
a(n) = LCM { tau(1), ..., tau(n) }, a(0) = 1.
2
1, 1, 2, 2, 6, 6, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 60, 60, 60, 60, 60, 60, 60, 60, 120, 120, 120, 120, 120, 120, 120, 120, 120, 120, 120, 120, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360, 360
OFFSET
0,3
COMMENTS
From Antti Karttunen, Aug 23 2017: (Start)
a(0) = 1 as an empty product.
Records (new values) occur at positions: 0, 2, 4, 6, 24, 36, 64, 120, 840, 900, 1024, 1296, 4096, 7560, ...
(End)
MATHEMATICA
Block[{nn = 60, s}, s = DivisorSigma[0, Range@ nn]; {1}~Join~Table[LCM @@ s[[1 ;; n]], {n, nn}]] (* Michael De Vlieger, Aug 23 2017 *)
PROG
(Scheme, with memoization-macro definec) (definec (A051548 n) (if (<= n 1) 1 (lcm (A000005 n) (A051548 (- n 1))))) ;; Antti Karttunen, Aug 23 2017
CROSSREFS
Cf. A000005.
Sequence in context: A241380 A028476 A179478 * A110660 A332759 A139550
KEYWORD
nonn
EXTENSIONS
a(0) = 1 prepended and the offset of the rest of terms corrected by Antti Karttunen, Aug 23 2017
STATUS
approved