A035075 -id:A035075 - cp's OEIS frontend

A035076 a(n) is root of square starting with digit 9: first term of runs.

30, 95, 300, 949, 3000, 9487, 30000, 94869, 300000, 948684, 3000000, 9486833, 30000000, 94868330, 300000000, 948683299, 3000000000, 9486832981, 30000000000, 94868329806, 300000000000, 948683298051, 3000000000000

Offset: 2

Patrick De Geest, Nov 15 1998

Cf. A067479 (squares), A017936.

Cf. 2: A035069, 3: A035070, 4: A035071, 5: A035072, 6: A035073, 7: A035074, 8: A035075.

Ceiling[Sqrt[9*10^Range[2,30]]] (* Harvey P. Dale, Aug 07 2013 *)

a(n) = ceiling(sqrt(9*10^n)), n > 1.

A045862 Numbers whose square has initial digit '8'.

Original entry on oeis.org

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

Jeff Burch

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

Cf. A045792, A035075.

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

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

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

A067478 Smallest n-digit square starting with 8.

Original entry on oeis.org

81, 841, 8100, 80089, 801025, 8003241, 80013025, 800041225, 8000050249, 80000162649, 800001447184, 8000004951184, 80000001609984, 800000042569984, 8000000160998400, 80000000297200369, 800000000000150481, 8000000001435765625, 80000000000015048100

Offset: 2

Amarnath Murthy, Feb 09 2002

Cf. A000290, A035075 (roots), A045791, A067479 (2..9).

nS[n_] := Module[{lr = Floor[Sqrt[n]]}, If[lr^2==n, lr^2, (lr + 1)^2]]; Table[nS[8 10^i], {i, 0, 20}]

a(n) = ceiling(sqrt(8*10^(n-1)))^2. - Sascha Kurz, Mar 18 2002

More terms from Harvey P. Dale, Feb 17 2002

Incorrect a(1) removed by Jon E. Schoenfield, Mar 21 2021

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A035076 a(n) is root of square starting with digit 9: first term of runs.

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A045862 Numbers whose square has initial digit '8'.

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A067478 Smallest n-digit square starting with 8.

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