A338248 Nonnegative values in A053985, in order of appearance.

0, 1, 4, 5, 2, 3, 16, 17, 14, 15, 20, 21, 18, 19, 8, 9, 6, 7, 12, 13, 10, 11, 64, 65, 62, 63, 68, 69, 66, 67, 56, 57, 54, 55, 60, 61, 58, 59, 80, 81, 78, 79, 84, 85, 82, 83, 72, 73, 70, 71, 76, 77, 74, 75, 32, 33, 30, 31, 36, 37, 34, 35, 24, 25, 22, 23, 28, 29

Offset

0,3

Comments

This sequence is a self-inverse permutation of the nonnegative integers (the offset has been set to 0 so as to get a permutation).

There are only two fixed points: a(0) = 0 and a(1) = 1.

Links

Rémy Sigrist, Table of n, a(n) for n = 0..5461

Index entries for sequences that are permutations of the natural numbers

Formula

a(0) = 0.

a(n) = A053985(A053738(n)) for any n > 0.

Example

A053985 = 0, 1, -2, -1, 4, 5, 2, 3, -8, -7, -10, -9, -4, -3, -6, -5, 16, 17, ...
We keep:  0, 1,         4, 5, 2, 3,                                  16, 17, ...

Prog

(PARI) A053985(n) = fromdigits(binary(n), -2)
print (select(v -> v>=0, apply(A053985, [0..109])))

Crossrefs

See A338245 for a similar sequence.

Cf. A053738, A053985, A338249.

Sequence in context: A216252 A335615 A328622 * A328623 A225901 A354469

Adjacent sequences: A338245 A338246 A338247 * A338249 A338250 A338251

Keyword

nonn,base

Author

Rémy Sigrist, Oct 18 2020

Status

approved