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A087226
LCM of terms in Collatz (3x+1) function initiated at n.
6
1, 2, 240, 4, 80, 240, 1361360, 8, 12252240, 80, 194480, 240, 1040, 1361360, 4095840, 16, 17680, 12252240, 107158480, 80, 1344, 194480, 1365280, 240, 535792400, 1040, 44841486948146266934850832405421294927083491752830032389039800908293040266400
OFFSET
1,2
EXAMPLE
n=9: list={9,28,14,7,22,11,34,17,52,26,13,40,20,10,5,16,8,4,2,1};
LCM = 2*2*2*2*3*3*5*7*11*13*17 = 12252240.
MATHEMATICA
c[x_] := (1-Mod[x, 2])*(x/2)+Mod[x, 2]*(3*x+1); c[1]=1; fpl[x_] := Delete[FixedPointList[c, x], -1] Table[Apply[LCM, fpl[w]], {w, 1, 32}]
Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; Table[LCM @@ Collatz[n], {n, 27}] (* T. D. Noe, May 15 2013 *)
PROG
(Haskell)
a087226 = foldl1 lcm . a070165_row -- Reinhard Zumkeller, May 16 2013
CROSSREFS
Cf. A006370.
Sequence in context: A013473 A212839 A225784 * A217972 A071967 A024348
KEYWORD
nonn
AUTHOR
Labos Elemer, Aug 28 2003
STATUS
approved