A045862 Numbers whose square has initial digit '8'.

9, 29, 90, 91, 92, 93, 94, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 895, 896, 897, 898, 899, 900, 901, 902, 903, 904, 905, 906, 907, 908, 909, 910, 911, 912, 913, 914, 915, 916, 917, 918, 919, 920, 921, 922, 923

Offset: 1

Author

Jeff Burch

Keywords

• nonn
• base

Links

• Seiichi Manyama, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A045792, A035075.

Programs

Mathematica

Select[Range[1000],Take[IntegerDigits[#^2],1]=={8}&] (* Harvey P. Dale, Jul 30 2019 *)

PARI

isok(k) = digits(k^2)[1] == 8; \\ Michel Marcus, Sep 29 2021

Python

from math import isqrt
def auptorun(runs):
    alst = []
    for n in range(1, runs+1):
        alst.extend(list(range(isqrt(8*10**n) + 1, isqrt(9*10**n - 1)+1)))
    return alst
print(auptorun(5)) # Michael S. Branicky, Sep 29 2021