A117073 Sequence of which A078783 is the Recamán transform.

0, 1, 2, 3, 4, 5, 6, 9, 10, 11, 20, 21, 22, 40, 41, 42, 82, 83, 84, 166, 167, 168, 334, 335, 336, 670, 671, 672, 1340, 1341, 1342, 2682, 2683, 2684, 5366, 5367, 5368, 10734, 10735, 10736, 21470, 21471, 21472, 42942, 42943, 42944, 85886, 85887, 85888

Offset: 0

Author

N. J. A. Sloane, Apr 17 2006

Keywords

• nonn

Comments

The d() sequence mentioned in A078783. Absolute values of first differences of A078783.

References

• N. J. A. Sloane and Allan Wilks, On sequences of Recaman type, paper in preparation, 2006.

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A078783.

Programs

Haskell

a117073 n = a117073_list !! n
-- a117073_list defined in A078783.  -- Reinhard Zumkeller, May 01 2015

Mathematica

b[0] = 0; b[1] = 1;
b[n_] := b[n] = For[m = 2, True, m++, If[FreeQ[Array[b, n-1], m], If[Abs[m - b[n-1]] > Abs[b[n-1] - b[n-2]], Return[m]]]];
a[0] = 0; a[n_] := a[n] = Abs[b[n] - b[n-1]];
Table[Print["a(", n, ") = ", a[n]]; a[n], {n, 0, 50}] (* Jean-François Alcover, Aug 02 2018 *)