A084471 Change 0 to 00 in binary representation of n.

1, 4, 3, 16, 9, 12, 7, 64, 33, 36, 19, 48, 25, 28, 15, 256, 129, 132, 67, 144, 73, 76, 39, 192, 97, 100, 51, 112, 57, 60, 31, 1024, 513, 516, 259, 528, 265, 268, 135, 576, 289, 292, 147, 304, 153, 156, 79, 768, 385, 388, 195, 400, 201, 204, 103, 448, 225

Offset

1,2

Comments

a(n) = n iff n = 2^k - 1, k>0.

A023416(a(n))=A023416(n)*2; A000120(a(n))=A000120(n);

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Formula

a(1)=1, a(2*k+1)=2*a(k)+1, a(2*k)=4*a(k).

Maple

a:= n-> Bits[Join](subs(0=[0$2][], Bits[Split](n))):
seq(a(n), n=1..60);  # Alois P. Heinz, Jan 15 2021

Mathematica

f[n_] := FromDigits[Flatten[IntegerDigits[n, 2] /. {0 -> {0, 0}}], 2]; Array[f, 60] (* Robert G. Wilson v, Dec 10 2009 *)

Prog

(Haskell)
a084471 1 = 1
a084471 x = 2 * (2 - d) * a084471 x' + d  where (x', d) = divMod x 2
-- Reinhard Zumkeller, Jul 16 2012

Crossrefs

Cf. A084472(n)=A007088(a(n)), A084473, A038573.

Ordered terms are in A060142.

Column k=2 of A340666.

Cf. A088698, A175047. - Robert G. Wilson v, Dec 10 2009

Sequence in context: A062776 A269512 A270128 * A285122 A277773 A277800

Adjacent sequences: A084468 A084469 A084470 * A084472 A084473 A084474

Keyword

nonn,look,base

Author

Reinhard Zumkeller, May 27 2003

Status

approved