A023967 - OEIS

A023967

First digit after decimal point of 8th root of n.

0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,5

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

Array[ Function[ n, RealDigits[ N[ Power[ n, 1/8 ], 10 ], 10 ]// (#[ [ 1, #[ [ 2 ] ]+1 ] ])& ], 110 ]

Table[Mod[Floor[10N[Surd[n, 8]]], 10], {n, 130}] (* Harvey P. Dale, Apr 11 2020 *)

PROG

(Python)

from sympy import integer_nthroot

def A023967(n): return integer_nthroot(n*10**8, 8)[0]%10 # Chai Wah Wu, Feb 27 2023