A330090 Inverse permutation to A330081.

0, 1, 2, 3, 4, 6, 5, 7, 8, 12, 9, 13, 10, 14, 11, 15, 16, 24, 18, 26, 17, 25, 19, 27, 20, 28, 22, 30, 21, 29, 23, 31, 32, 48, 36, 52, 33, 49, 37, 53, 34, 50, 38, 54, 35, 51, 39, 55, 40, 56, 44, 60, 41, 57, 45, 61, 42, 58, 46, 62, 43, 59, 47, 63, 64, 96, 72

Offset

0,3

Comments

If the binary expansion of n is (b(1), ..., b(w)), then the binary expansion of a(n) is (b(1), b(w), b(2), b(w-1), ...); this corresponds to a "milk shuffle".

Links

Rémy Sigrist, Table of n, a(n) for n = 0..8192

Index entries for sequences related to binary expansion of n

Index entries for sequences that are permutations of the natural numbers

Example

A330081(19) = 22, hence a(22) = 19.

Prog

(PARI) unshuffle(v) = { my (w=vector(#v), o=0, e=#v+1); for (k=1, #v, w[k]=v[if (k%2, o++, e--)]); w }
a(n) = fromdigits(unshuffle(binary(n)), 2)

Crossrefs

Cf. A330081.

Sequence in context: A343152 A267105 A080542 * A072758 A104464 A352725

Adjacent sequences: A330087 A330088 A330089 * A330091 A330092 A330093

Keyword

nonn,base

Author

Rémy Sigrist, Dec 01 2019

Status

approved