A185679 Number of digits in decimal expansion of n^2.

1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5

Offset

0,5

Links

G. C. Greubel, Table of n, a(n) for n = 0..5000

Formula

a(n) = 1 + floor(log(10, n^2)) for n>0.

Example

a(33)=4 since 33^2=1089 has 4 digits.

Mathematica

Table[Length[IntegerDigits[n^2]], {n, 0, 100}]
Join[{1}, IntegerLength[Range[100]^2]] (* Harvey P. Dale, Sep 17 2019 *)

Prog

(PARI) concat([1], for(n=1, 50, print1(1 + floor(log(n^2)/log(10)), ", "))) \\ G. C. Greubel, Jul 10 2017
(Python)
def A185679(n): return len(str(n**2)) # Chai Wah Wu, Mar 15 2023

Crossrefs

Cf. A055642.

Sequence in context: A320857 A211664 A182434 * A366721 A080342 A081604

Adjacent sequences: A185676 A185677 A185678 * A185680 A185681 A185682

Keyword

nonn,base

Author

Carmine Suriano, Feb 23 2011

Status

approved