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A215728
a(n) is the smallest m for which 5^m contains n consecutive identical digits.
14
0, 11, 50, 95, 125, 1087, 2786, 2790, 2796, 2797, 2802, 2803, 1040703, 5547565, 7761841, 17876345
OFFSET
1,2
COMMENTS
a(13) > 893000. - Chai Wah Wu, Dec 17 2014
PROG
(Python)
def A215728(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 *= 5
return 'search limit reached'
# Chai Wah Wu, Dec 17 2014
CROSSREFS
Sequence in context: A241964 A306425 A241406 * A185019 A212560 A341735
KEYWORD
nonn,base,more
AUTHOR
V. Raman, Aug 22 2012
EXTENSIONS
a(13)-a(14) from Giovanni Resta, Apr 19 2016
a(15)-a(16) from Bert Dobbelaere, Feb 13 2019
STATUS
approved