A035070 a(n) is root of square starting with digit 3: first term of runs.

6, 18, 55, 174, 548, 1733, 5478, 17321, 54773, 173206, 547723, 1732051, 5477226, 17320509, 54772256, 173205081, 547722558, 1732050808, 5477225576, 17320508076, 54772255751, 173205080757, 547722557506, 1732050807569, 5477225575052, 17320508075689, 54772255750517

Offset: 1

Author

Patrick De Geest, Nov 15 1998

Keywords

• nonn
• base

Links

• Michael S. Branicky, Table of n, a(n) for n = 1..1999

Crossrefs

Cf. A067473 (squares), A035076 (2..9).

Programs

Mathematica

Table[Ceiling @ Sqrt[3 * 10^n], {n, 1, 24}] (* Amiram Eldar, Oct 08 2019 *)

Python

from math import isqrt
def a(n): return isqrt(3*10**n) + 1
print([a(n) for n in range(1, 28)]) # Michael S. Branicky, Jun 18 2021

Formula

a(n) = ceiling(sqrt(3*10^n)).

Extensions

Offset 1 from Alois P. Heinz, Oct 08 2019