A087261 a(n) = lcm(4n, A025586(4n)), least common multiple of 4n and the largest value in 3x+1 iteration list started at 4n.

4, 8, 48, 16, 20, 24, 364, 32, 468, 40, 572, 48, 52, 56, 480, 64, 68, 72, 1672, 80, 84, 88, 3680, 96, 100, 104, 249264, 112, 116, 480, 286192, 128, 132, 136, 1120, 144, 148, 152, 11856, 160, 378512, 168, 8428, 176, 180, 184, 433904, 192, 196, 200, 11832, 208, 212

Offset: 1

Author

Labos Elemer, Sep 09 2003

Keywords

• nonn

Links

• Index entries for sequences related to 3x+1 (or Collatz) problem

Crossrefs

Cf. A025586, A033496, A087260.

Programs

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[LCM[4*w, Max[fpl[4*w]]], {w, 1, 256}]