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!)
A242347 Number of decimal digits of A008559. 2
1, 2, 4, 10, 31, 100, 330, 1093, 3628, 12049, 40023, 132951, 441651, 1467130, 4873698, 16190071, 53782249, 178660761, 593498199, 1971558339 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(n+1)/a(n) is approximately log_2(10) = A020862. - André Engels, Apr 01 2021
LINKS
Code Golf StackExchange, Length of Binary as Base 10 [OEIS A242347], coding challenge started Oct 28 2022.
FORMULA
a(n) = A055642(A008559(n)). - Michel Marcus, May 11 2014
EXAMPLE
a(3) = 4 because 1010 has 4 decimal digits.
PROG
(Python)
A242347_list, l = [1], 2
for _ in range(10):
....l = int(bin(l)[2:])
....A242347_list.append(len(str(l))) # Chai Wah Wu, Dec 26 2014
(PARI) a242347(n) = {my (k=2, d=digits); while(n--, k=fromdigits(d(k, 2))); #d(k)} \\ Hugo Pfoertner, Nov 04 2022
CROSSREFS
Sequence in context: A001647 A007177 A328815 * A138415 A005268 A243931
KEYWORD
nonn,base,more
AUTHOR
J. Lowell, May 11 2014
EXTENSIONS
a(1), a(18)-a(20) from Chai Wah Wu, Dec 26 2014
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 July 17 05:50 EDT 2024. Contains 374360 sequences. (Running on oeis4.)