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A084471 Change 0 to 00 in binary representation of n. 8
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 (list; graph; refs; listen; history; text; internal format)
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).

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.

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

Sequence in context: A062776 A269512 A270128 * A277773 A277800 A278469

Adjacent sequences:  A084468 A084469 A084470 * A084472 A084473 A084474

KEYWORD

nonn,look

AUTHOR

Reinhard Zumkeller, May 27 2003

STATUS

approved

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Last modified December 4 17:40 EST 2016. Contains 278755 sequences.