A033492 Record number of steps to reach 1 in '3x+1' problem, corresponding to starting values in A006877 (same as A006878 except here we start counting at 1 instead of 0).

1, 2, 8, 9, 17, 20, 21, 24, 112, 113, 116, 119, 122, 125, 128, 131, 144, 145, 171, 179, 182, 183, 209, 217, 238, 262, 268, 276, 279, 282, 308, 311, 324, 340, 351, 354, 375, 383, 386, 443, 449, 470, 509, 525, 528, 531, 557, 560, 563, 584, 597, 613, 665, 686

Offset

1,2

Comments

Both the 3x+1 steps and the halving steps are counted.

References

R. E. Maeder, Programming in Mathematica, 3rd Edition, Addison-Wesley, pages 251-252.

Links

T. D. Noe, Table of n, a(n) for n=1..130 (from Eric Roosendaal's data)

Eric Roosendaal, 3x+1 Delay Records

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

Crossrefs

Equal to A006878 + 1. Cf. A006884, A006885, A033492.

Sequence in context: A105125 A230314 A220263 * A126160 A118962 A096033

Adjacent sequences: A033489 A033490 A033491 * A033493 A033494 A033495

Keyword

nonn

Author

Jeff Burch

Extensions

Corrected and extended by Lee Corbin (lcorbin(AT)tsoft.com)

More terms from Larry Reeves (larryr(AT)acm.org), Apr 27 2001

Status

approved