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A215729
a(n) is the smallest m for which 6^m contains (at least) n consecutive identical digits.
14
0, 5, 5, 115, 226, 371, 1503, 8533, 27717, 27717, 69936, 848255, 1308931, 8255246, 32564822, 39063403
OFFSET
1,2
COMMENTS
a(12) > 838000. - Chai Wah Wu, Dec 17 2014
a(14) > 7*10^6. - Giovanni Resta, Apr 20 2016
PROG
(Python)
def A215729(n):
l, x = [str(d)*n for d in range(10)], 1
for m in range(10**9):
s = str(x)
for k in l:
if k in s:
return m
x *= 6
return 'search limit reached'
# Chai Wah Wu, Dec 17 2014
CROSSREFS
Sequence in context: A048607 A229767 A369753 * A364452 A094463 A055928
KEYWORD
nonn,base,more,hard
AUTHOR
V. Raman, Aug 22 2012
EXTENSIONS
a(11) from Rick van der Hoorn, Mar 26 2013
a(12)-a(13) from Giovanni Resta, Apr 19 2016
a(14) from Bert Dobbelaere, Feb 15 2019
a(15) from Paul Geneau de Lamarlière, May 26 2024
a(16) from Paul Geneau de Lamarlière, Jul 12 2024
STATUS
approved