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A135698 Palindromes with odd number of digits formed from the reflected decimal expansion of Pi. 4
3, 313, 31413, 3141413, 314151413, 31415951413, 3141592951413, 314159262951413, 31415926562951413, 3141592653562951413, 314159265353562951413, 31415926535853562951413, 3141592653589853562951413, 314159265358979853562951413, 31415926535897979853562951413 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Pi = 3.14159265358979323846264338327... (see A000796).
The number of digits of a(n) is equal to 2n - 1.
The first five members of this sequence are in the example of A119351.
LINKS
EXAMPLE
n ........... a(n)
1 ............ 3
2 ........... 313
3 .......... 31413
4 ......... 3141413
5 ........ 314151413
6 ....... 31415951413
7 ...... 3141592951413
8 ..... 314159262951413
9 .... 31415926562951413
10 .. 3141592653562951413
MATHEMATICA
pinxt[n_]:=With[{pid=RealDigits[Pi, 10, 20][[1]]}, Module[{a=Take[pid, n]}, FromDigits[Join[a, Reverse[Most[a]]]]]]; Table[pinxt[n], {n, 1, 15}] (* Harvey P. Dale, Oct 06 2011 *)
CROSSREFS
Sequence in context: A306140 A317373 A083974 * A360803 A088102 A039954
KEYWORD
base,nonn
AUTHOR
Omar E. Pol, Mar 01 2008, Mar 28 2008
EXTENSIONS
More terms from Harvey P. Dale, Oct 06 2011
STATUS
approved

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Last modified July 12 17:26 EDT 2024. Contains 374251 sequences. (Running on oeis4.)