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A030697
Smallest nontrivial extension of n-th cube which is a cube not ending 000.
2
125, 85184, 2744, 6434856, 1259712, 2161700757, 34328125, 5124031424, 7290099019, 10007873875, 13312053, 172808693, 21975528401, 274498269499, 337589698347, 409675763483, 491355848971, 58320792152, 68593724400375
OFFSET
1,1
PROG
(Python)
from gmpy2 import iroot
def A030697(n):
d, nd = 10, 10*n**3
while True:
x = iroot(nd-1, 3)[0]+1
if not x % 10:
x += 1
x = x**3
if x < nd+d:
return int(x)
d *= 10
nd *= 10 # Chai Wah Wu, May 24 2016
CROSSREFS
Cf. A030698.
Sequence in context: A194654 A222277 A013783 * A265623 A050640 A161354
KEYWORD
nonn,base
STATUS
approved