A092323 2^m - 1 appears 2^m times.

0, 1, 1, 3, 3, 3, 3, 7, 7, 7, 7, 7, 7, 7, 7, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63

Offset

1,4

Comments

Or, write n in binary and change the most significant bit to 0 and all other bits to 1.

a(n) = A053644(n) - 1 = A003817(n) - A053644(n).

a(n) = floor(A003817(n-1)/2). [Reinhard Zumkeller, Jul 18 2010]

Links

Table of n, a(n) for n=1..74.

Formula

a(n) = if n=1 then 0 else a(floor(n/2))*2 + 1.

a(1)=0, a(2n) = 2*a(n)+1, a(2n+1) = a(2n). - Ralf Stephan, Nov 18 2010

Mathematica

Table[FromDigits[#, 2] &@ Table[1, {IntegerLength[n, 2] - 1}], {n, 80}] (* Michael De Vlieger, Jun 26 2016 *)
Table[Table[2^m-1, 2^m], {m, 0, 6}]//Flatten (* Harvey P. Dale, May 22 2021 *)

Prog

(Magma) [n le 2 select n-1 else Self(Floor(n/2))*2+1: n in [1..100]]; // Vincenzo Librandi, Jun 27 2016

Crossrefs

Cf. A003817, A053644.

Sequence in context: A195758 A304684 A079084 * A339053 A244584 A369233

Adjacent sequences: A092320 A092321 A092322 * A092324 A092325 A092326

Keyword

nonn,easy

Author

Reinhard Zumkeller, Feb 15 2004

Status

approved