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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A256521 Table T(n, k) of positions p[i] where number n occurs after the decimal point in the decimal expansion of Pi, read by antidiagonals.

Original entry on oeis.org

32, 50, 1, 54, 3, 6, 65, 37, 16, 9, 71, 40, 21, 15, 2, 77, 49, 28, 17, 19, 4, 85, 68, 33, 24, 23, 8, 7, 97, 94, 53, 25, 36, 10, 20, 13, 106, 95, 63, 27, 57, 31, 22, 29, 11, 116, 103, 73, 43, 59, 48, 41, 39, 18, 5, 121, 110, 76, 46, 60, 51, 69, 47, 26, 12, 49, 128, 138, 83, 64, 70, 61, 72, 56, 34, 14, 163, 94
Offset: 0

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Author

Felix Fröhlich, Apr 01 2015

Keywords

Comments

Table T(n, k) starts:
n = 0: 32, 50, 54, 65, 71, 77, 85, 97, 106, 116, ...
n = 1: 1, 3, 37, 40, 49, 68, 94, 95, 103, 110, ...
n = 2: 6, 16, 21, 28, 33, 53, 63, 73, 76, 83, ...
n = 3: 9, 15, 17, 24, 25, 27, 43, 46, 64, 86, ...
n = 4: 2, 19, 23, 36, 57, 59, 60, 70, 87, 92, ...
n = 5: 4, 8, 10, 31, 48, 51, 61, 90, 109, 130, ...
n = 6: 7, 20, 22, 41, 69, 72, 75, 82, 98, 108, ...
n = 7: 13, 29, 39, 47, 56, 66, 96, 99, 120, 139, ...
n = 8: 11, 18, 26, 34, 35, 52, 67, 74, 78, 81, ...
n = 9: 5, 12, 14, 30, 38, 42, 44, 45, 55, 58, ...
n = 10: 49, 163, 175, 206, 269, 442, 681, 780, 852, 854, ...
...

Examples

			T(6, 4) = 41, since the fourth occurrence of 6 in the decimal expansion of Pi is at position 41.
		

Crossrefs

Cf. A000796 (Pi), A014777 (first column).
Cf. A037008, A037000, A037001, A037002, A037003 (0th to 4th row).
Cf. A037004, A037005, A036974, A037006, A037007 (5th to 9th row).

Programs

  • Mathematica
    spi = StringDrop[ ToString[ N[ Pi, 1000]], 2]; t[n_, k_] := StringPosition[ spi, ToString[n], k][[-1, 1]]; Table[ t[n - k, k], {n, 0, 12}, {k, n, 1, -1}] // Flatten (* Robert G. Wilson v, Apr 07 2015 *)

Extensions

More terms from Robert G. Wilson v, Apr 07 2015