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A331560 Size of the palindrome-free intervals about the 196-iterates, A006960. 2
11, 10, 110, 110, 100, 100, 110, 1100, 1000, 11000, 11000, 11000, 11000, 10000, 10000, 10000, 11000, 110000, 110000, 100000, 100000, 1100000, 1100000, 1100000, 1000000, 1000000, 11000000, 11000000, 10000000, 10000000, 110000000, 110000000, 110000000, 100000000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
By empirical observation, the integers in this sequence are of the form 10*10^n and 11*10^n, n >= 0, since they are the difference of consecutive palindromes surrounding the 196-iterates. (No differences of 2 observed.)
LINKS
FORMULA
a(n) = A331556(n) + A331557(n).
EXAMPLE
191 < 196 < 202, 202 - 191 = 11;
878 < 887 < 888, 888 - 878 = 10; etc.
PROG
(Python)
# Palindrome-free interval about 196 offsets. Slow brute-force
n = 196
while n < 10**15:
m = n
while m != int(str(m)[::-1]): m+=1
s = m
m = n
while m != int(str(m)[::-1]): m-=1
print(s-m)
n = n + int(str(n)[::-1])
CROSSREFS
Sequence in context: A304747 A304749 A105028 * A014550 A367547 A070836
KEYWORD
nonn,base
AUTHOR
_James D. Klein_, Jan 20 2020
EXTENSIONS
a(31)-a(34) from _Jinyuan Wang_, Feb 29 2020
STATUS
approved

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Last modified March 5 06:47 EST 2024. Contains 370537 sequences. (Running on oeis4.)