login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A054868 Sum of bits of sum of bits of n: a(n) = wt(wt(n)). 4
0, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 2, 1, 1, 1, 1, 2, 1, 2, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 1, 1, 2, 1, 2, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, 1, 1, 2, 1, 2, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,8

COMMENTS

a(n) = A000120(A000120(n)).

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

R. Bellman and H. N. Shapiro, On a problem in additive number theory, Annals Math., 49 (1948), 333-340.

Michael Gilleland, Some Self-Similar Integer Sequences

Index entries for sequences related to binary expansion of n

EXAMPLE

a(127) = 3 since 127 in base 2 is 1111111, whose sum of bits is 7 and 7 in base 2 is 111, whose sum of bits is 3

PROG

(PARI) a(n) = norml2(binary(norml2(binary(n))))  \\ Michel Marcus, May 25 2013

(Haskell)

a054868 = a000120 . a000120  -- Reinhard Zumkeller, Mar 31 2015

CROSSREFS

Cf. A000120, A089224.

Sequence in context: A319608 A230850 A072085 * A065081 A212185 A270928

Adjacent sequences:  A054865 A054866 A054867 * A054869 A054870 A054871

KEYWORD

nonn

AUTHOR

Jeffrey Shallit, May 15 2000

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 16 07:59 EDT 2021. Contains 343030 sequences. (Running on oeis4.)