A008875 3x+1 sequence starting at 95.

95, 286, 143, 430, 215, 646, 323, 970, 485, 1456, 728, 364, 182, 91, 274, 137, 412, 206, 103, 310, 155, 466, 233, 700, 350, 175, 526, 263, 790, 395, 1186, 593, 1780, 890, 445, 1336, 668, 334, 167, 502, 251, 754, 377, 1132, 566, 283, 850, 425, 1276, 638, 319, 958, 479, 1438, 719, 2158, 1079, 3238

Offset

0,1

References

R. K. Guy, Unsolved Problems in Number Theory, E16.

Links

T. D. Noe, Table of n, a(n) for n=0..105

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

Formula

a(n) = A008874(n + 2).

Maple

f := proc(n) option remember; if n = 0 then 95; elif f(n-1) mod 2 = 0 then f(n-1)/2 else 3*f(n-1)+1; fi; end;

Mathematica

NestList[If[EvenQ[#], #/2, 3#+1]&, 95, 60] (* Harvey P. Dale, Dec 02 2012 *)

Prog

(Haskell)
a008875 n = a008875_list !! n
a008875_list = drop 2 a008874_list
-- Reinhard Zumkeller, Aug 30 2012
(Magma) [n eq 1 select 95 else IsOdd(Self(n-1)) select 3*Self(n-1)+1 else Self(n-1) div 2: n in [1..70]]; // Vincenzo Librandi, Jul 29 2014

Crossrefs

Cf. A006370, A008874.

Row 95 of A347270.

Sequence in context: A116113 A051400 A225931 * A174157 A200882 A217133

Adjacent sequences: A008872 A008873 A008874 * A008876 A008877 A008878

Keyword

nonn

Author

N. J. A. Sloane.

Extensions

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

Status

approved