A090640 a(0) = 0; a(2n) = 4*a(n), a(2n+1) = a(n) + 1.

0, 1, 4, 2, 16, 5, 8, 3, 64, 17, 20, 6, 32, 9, 12, 4, 256, 65, 68, 18, 80, 21, 24, 7, 128, 33, 36, 10, 48, 13, 16, 5, 1024, 257, 260, 66, 272, 69, 72, 19, 320, 81, 84, 22, 96, 25, 28, 8, 512, 129, 132, 34, 144, 37, 40, 11, 192, 49, 52, 14, 64, 17, 20, 6, 4096, 1025, 1028, 258, 1040

Offset

0,3

Links

Table of n, a(n) for n=0..68.

N. J. A. Sloane and J. A. Sellers, On non-squashing partitions, arXiv:math/0312418 [math.CO], 2003.

N. J. A. Sloane and J. A. Sellers, On non-squashing partitions, Discrete Math., 294 (2005), 259-274.

Maple

S := 4; f := proc(n) global S; option remember; if n=0 then RETURN(0); fi; if n mod 2 = 0 then RETURN(S*f(n/2)); else f((n-1)/2)+1; fi; end;

Mathematica

a[n_] := a[n] = Which[n == 0, 0, EvenQ[n], 4 a[n/2], True, a[(n-1)/2] + 1];
Table[a[n], {n, 0, 68}] (* Jean-François Alcover, Nov 28 2017 *)

Crossrefs

Cf. A087808, A090639.

Sequence in context: A130042 A285362 A109922 * A302213 A090881 A191452

Adjacent sequences: A090637 A090638 A090639 * A090641 A090642 A090643

Keyword

nonn

Author

N. J. A. Sloane, Dec 14 2003

Status

approved