login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A083652 Sum of lengths of binary expansions of 0 through n. 18
1, 2, 4, 6, 9, 12, 15, 18, 22, 26, 30, 34, 38, 42, 46, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 136, 142, 148, 154, 160, 166, 172, 178, 184, 190, 196, 202, 208, 214, 220, 226, 232, 238, 244, 250, 256, 262, 268, 274, 280, 286, 292 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
a(n) = A001855(n) + 1 for n > 0;
a(0) = A070939(0)=1, n > 0: a(n) = a(n-1) + A070939(n).
A030190(a(k))=1; A030530(a(k)) = k + 1.
Partial sums of A070939. - Hieronymus Fischer, Jun 12 2012
Young writes "If n = 2^i + k [...] the maximum is (i+1)(2^i+k)-2^{i+1}+2." - Michael Somos, Sep 25 2012
LINKS
Hsien-Kuei Hwang, S. Janson, and T.-H. Tsai, Exact and Asymptotic Solutions of a Divide-and-Conquer Recurrence Dividing at Half: Theory and Applications, ACM Transactions on Algorithms, 13:4 (2017), #47; DOI: 10.1145/3127585.
Hsien-Kuei Hwang, Svante Janson, and Tsung-Hsi Tsai, Identities and periodic oscillations of divide-and-conquer recurrences splitting at half, arXiv:2210.10968 [cs.DS], 2022, p. 36.
Alfred Young, The Maximum Order of an Irreducible Covariant of a System of Binary Forms, Proc. Roy. Soc. 72 (1903), 399-400 = The Collected Papers of Alfred Young, 1977, 136-137.
FORMULA
a(n) = 2 + (n+1)*ceiling(log_2(n+1)) - 2^ceiling(log_2(n+1)).
G.f.: g(x) = 1/(1-x) + (1/(1-x)^2)*Sum_{j>=0} x^2^j. - Hieronymus Fischer, Jun 12 2012; corrected by Ilya Gutkovskiy, Jan 08 2017
a(n) = A123753(n) - n. - Peter Luschny, Nov 30 2017
EXAMPLE
G.f. = 1 + 2*x + 4*x^2 + 6*x^3 + 9*x^4 + 12*x^5 + 15*x^6 + 18*x^7 + 22*x^8 + ...
MATHEMATICA
Accumulate[Length/@(IntegerDigits[#, 2]&/@Range[0, 60])] (* Harvey P. Dale, May 28 2013 *)
a[n_] := (n + 1) IntegerLength[n + 1, 2] - 2^IntegerLength[n + 1, 2] + 2; Table[a[n], {n, 0, 58}] (* Peter Luschny, Dec 02 2017 *)
PROG
(Haskell)
a083652 n = a083652_list !! n
a083652_list = scanl1 (+) a070939_list
-- Reinhard Zumkeller, Jul 05 2012
(PARI) {a(n) = my(i); if( n<0, 0, n++; i = length(binary(n)); n*i - 2^i + 2)}; /* Michael Somos, Sep 25 2012 */
(PARI) a(n)=my(i=#binary(n++)); n*i-2^i+2 \\ equivalent to the above
(Python)
def A083652(n):
s, i, z = 1, n, 1
while 0 <= i: s += i; i -= z; z += z
return s
print([A083652(n) for n in range(0, 59)]) # Peter Luschny, Nov 30 2017
(Python)
def A083652(n): return 2+(n+1)*(m:=(n+1).bit_length())-(1<<m) # Chai Wah Wu, Mar 01 2023
CROSSREFS
A296349 is an essentially identical sequence.
Sequence in context: A130240 A143118 A162800 * A296349 A325544 A118103
KEYWORD
nonn,easy,base
AUTHOR
Reinhard Zumkeller, May 01 2003
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 30 17:05 EDT 2024. Contains 372139 sequences. (Running on oeis4.)