A242347 Number of decimal digits of A008559.

1, 2, 4, 10, 31, 100, 330, 1093, 3628, 12049, 40023, 132951, 441651, 1467130, 4873698, 16190071, 53782249, 178660761, 593498199, 1971558339

Offset

1,2

Comments

a(n+1)/a(n) is approximately log_2(10) = A020862. - André Engels, Apr 01 2021

Links

Table of n, a(n) for n=1..20.

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

Cf. A008559, A055642, A020862.

Sequence in context: A001647 A007177 A328815 * A138415 A005268 A243931

Adjacent sequences: A242344 A242345 A242346 * A242348 A242349 A242350

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