A138071 -id:A138071 - cp's OEIS frontend

A135697 Palindromes formed from the reflected decimal expansion of Pi.

3, 33, 313, 3113, 31413, 314413, 3141413, 31411413, 314151413, 3141551413, 31415951413, 314159951413, 3141592951413, 31415922951413, 314159262951413, 3141592662951413, 31415926562951413, 314159265562951413, 3141592653562951413, 31415926533562951413, 314159265353562951413

Offset: 1

Omar E. Pol, Mar 01 2008, Mar 28 2008

Pi = 3.14159265358979323846264338327... (see A000796).

The number of digits of a(n) is equal to n.

			   n        Digits of a(n)
   1             ( 3 )
   2            ( 3 3 )
   3           ( 3 1 3 )
   4          ( 3 1 1 3 )
   5         ( 3 1 4 1 3 )
   6        ( 3 1 4 4 1 3 )
   7       ( 3 1 4 1 4 1 3 )
   8      ( 3 1 4 1 1 4 1 3 )
   9     ( 3 1 4 1 5 1 4 1 3 )
  10    ( 3 1 4 1 5 5 1 4 1 3 )

Paolo Xausa, Table of n, a(n) for n = 1..900

Cf. A000796, A002113, A039954, A138070, A138071.

Table[FromDigits[Join[#[[;; Floor[n/2]]], #[[Ceiling[n/2] ;; 1 ;; -1]]]], {n, Length[#]}] & [First[RealDigits[Pi, 10, 25]]] (* Paolo Xausa, Dec 09 2024 *)

A138070 Triangle read by rows: row n lists the successive digits of A135697(n), the palindromic number formed from the reflected decimal expansion of Pi.

Original entry on oeis.org

3, 3, 3, 3, 1, 3, 3, 1, 1, 3, 3, 1, 4, 1, 3, 3, 1, 4, 4, 1, 3, 3, 1, 4, 1, 4, 1, 3, 3, 1, 4, 1, 1, 4, 1, 3, 3, 1, 4, 1, 5, 1, 4, 1, 3, 3, 1, 4, 1, 5, 5, 1, 4, 1, 3, 3, 1, 4, 1, 5, 9, 5, 1, 4, 1, 3, 3, 1, 4, 1, 5, 9, 9, 5, 1, 4, 1, 3, 3, 1, 4, 1, 5, 9, 2, 9, 5, 1, 4, 1, 3

Offset: 1

Omar E. Pol, Mar 03 2008

Also, successive digits of A135697(n).

			Triangle begins:
      3
     3,3
    3,1,3
   3,1,1,3
  3,1,4,1,3

Paolo Xausa, Table of n, a(n) for n = 1..11325 (rows 1..150 of triangle, flattened).

Decimal expansion of Pi: A000796. Cf. A135697, A135698, A138071.

Table[Join[#[[;; Floor[n/2]]], #[[Ceiling[n/2] ;; 1 ;; -1]]], {n, Length[#]}] & [First[RealDigits[Pi, 10, 15]]] (* Paolo Xausa, Dec 09 2024 *)

A138114 Triangle read by rows: row n lists the first n digits of the decimal expansion of Pi.

Original entry on oeis.org

3, 3, 1, 3, 1, 4, 3, 1, 4, 1, 3, 1, 4, 1, 5, 3, 1, 4, 1, 5, 9, 3, 1, 4, 1, 5, 9, 2, 3, 1, 4, 1, 5, 9, 2, 6, 3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8

Offset: 1

Omar E. Pol, Mar 14 2008

			Triangle begins:
..... 3
.... 3,1
... 3,1,4
.. 3,1,4,1
. 3,1,4,1,5

Cf. A000796, A138070, A138071.

s={};Do[AppendTo[s,RealDigits[Pi,10,n][[1]]],{n,12}];s//Flatten (* James C. McMahon, Jun 05 2025 *)

cp's OEIS Frontend

A135697 Palindromes formed from the reflected decimal expansion of Pi.

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A138070 Triangle read by rows: row n lists the successive digits of A135697(n), the palindromic number formed from the reflected decimal expansion of Pi.

Views

Author

Keywords

Comments

Examples

Links

Crossrefs

Programs

Mathematica

A138114 Triangle read by rows: row n lists the first n digits of the decimal expansion of Pi.

Views

Author

Keywords

Examples

Crossrefs

Programs

Mathematica