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A068046
Palindromes of length greater than 1 in decimal expansion of Pi (not showing leading 0's).
6
141, 535, 979, 323, 46264, 626, 33, 383, 88, 939, 3993, 99, 494, 44, 8998, 99, 11, 808, 32823, 282, 66, 44, 55, 505, 22, 535, 848, 11, 111, 11, 11, 55, 555, 55, 6446, 44, 22, 303, 44, 88, 5665, 66, 33, 44, 33, 19091, 909, 66, 454, 66, 33, 393, 141, 27372, 737, 0, 660, 66, 606, 55, 88, 88, 282, 292, 171, 0
OFFSET
1,1
COMMENTS
The n-th palindrome starts at A068047(n) and has length A068048(n).
Is this sequence well-defined? For example, how do we know that 141... is not the start of the some very long palindrome in Pi? - Sean A. Irvine, Jan 19 2024
LINKS
EXAMPLE
Pi = 3.141592653589793238462643383279502884197169399375 ...
a(2) = 535, as the second nontrivial palindrome in Pi is '535', starting at A068047(2) = 9 with length A068048(2) = 3.
MATHEMATICA
pi = RealDigits[ Pi, 10, 600][[1]]; palQ[n_] := n == Reverse[n]; k = 1; lst = {}; While[j = k + 1; k < 600, While[j < 600 - k, If[ palQ[ Take[pi, {k, j}]], p = FromDigits[ Take[ pi, {k, j}]]; AppendTo[ lst, p]; Print[p]]; j++]; k++]; lst Robert G. Wilson v, Jun 11 2013
CROSSREFS
KEYWORD
nonn,look,base
AUTHOR
Reinhard Zumkeller, Feb 11 2002
STATUS
approved