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A099052 All palindromes of length greater than 1 in the decimal expansion of e, ordered by the ending position of the palindrome. Multiple terms ending at the same position are ordered by the starting position of the palindrome. 2

%I #12 Jun 29 2021 02:33:30

%S 828,18281,818,28182,8281828,828,353,747,66,2662,77,757,99,999,99,959,

%T 595,66,9669,696,676,77,2772,66,303,353,535,525,66,66,919,39193,99,

%U 181,66,33,595,323,232,434,94349,323,33,88,525,101,11,383,99,88,4884,44

%N All palindromes of length greater than 1 in the decimal expansion of e, ordered by the ending position of the palindrome. Multiple terms ending at the same position are ordered by the starting position of the palindrome.

%H Michael S. Branicky, <a href="/A099052/b099052.txt">Table of n, a(n) for n = 1..10000</a>

%o (Python)

%o from sympy import E

%o def ispal(s): return all(s[i] == s[-1-i] for i in range(len(s)//2))

%o def aupto(maxdigs):

%o digits_e = str(E.n(maxdigs+4))[2:]

%o return [int(s) for s in (digits_e[j:k+1] for k in range(1, maxdigs)

%o for j in range(k)) if s[0] != '0' and ispal(s)]

%o print(aupto(240)) # _Michael S. Branicky_, Jun 28 2021

%Y Cf. A001113 (e).

%K nonn,base

%O 1,1

%A Matthew Howells (mathmatt(AT)gmail.com), Nov 13 2004

%E Offset changed and a(50) and beyond from _Michael S. Branicky_, Jun 28 2021

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Last modified October 4 11:16 EDT 2023. Contains 365874 sequences. (Running on oeis4.)