cp's OEIS Frontend

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.

Showing 1-6 of 6 results.

A102524 Continued fraction expansion of A102522.

Original entry on oeis.org

0, 1, 1, 1, 21, 1, 3, 36, 3, 1, 1, 6, 2, 1, 1, 1, 1, 3, 1, 44, 1, 3, 3, 4, 13, 1, 4, 7, 1, 1, 3, 1, 3, 1, 4, 2, 1, 1, 1, 17, 5, 1, 9, 1, 1, 6, 1, 6, 12, 3, 5, 1, 1, 8, 1, 3, 30, 1, 4, 4, 1, 2, 2, 7, 1, 7, 1, 16, 7, 8, 7, 1, 51, 1, 1, 1, 240, 7, 1, 2, 1, 1, 1, 7, 4, 1, 10, 19, 3, 1, 6, 1, 22, 1, 6, 1, 1, 2, 5
Offset: 0

Views

Author

Keywords

Comments

Increasing PQ's are: 1,21,36,44,51,240,298,999,2004,18156,130055, ...

Crossrefs

Cf. A100060, A102522 (decimal expansion).

Programs

  • Mathematica
    ContinuedFraction[ FromDigits[ {Join[{1}, Table[ If[ xx[[n]] > 0, 1, 0], {n, 1000}]], 0}, 2]]

Extensions

Offset changed by Andrew Howroyd, Aug 04 2024

A100060 a(n)=1 if the n-th second difference of the imaginary parts of the nontrivial zeros of the Riemann zeta function is positive, otherwise a(n)=0.

Original entry on oeis.org

1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1
Offset: 1

Views

Author

Gary W. Adamson, Oct 31 2004

Keywords

Comments

Differences between zeta function gaps: increases are 1 and decreases are 0.
The ratios of the numbers of 0's to the number of 1's in the first 10^n differences are 0/1, 5/5, 50/50, 493/507, 4998/5002, 49949/50049, ...

Examples

			The first few positive t values of the zeros 1/2+i*t are (14.13..., 21.02..., 25.01..., 30.42..., 32.93..., 37.58..., 40.91..., 43.32...).
First differences are (6.88..., 3.98..., 5.41..., 2.51..., 4.65..., 3.33..., 2.40...).
Second differences are (-2.89..., 1.42..., -2.90..., 2.14..., -1.31..., -0.92...) which yields (0, 1, 0, 1, 0, 0, ...).
		

Crossrefs

Programs

  • Mathematica
    zz = { (* the list of values in the link *) }; yy = Drop[zz, 1] - Drop[zz, -1]; Join[{1}, Table[ If[ yy[[n + 1]] > yy[[n]], 1, 0], {n, 104}]] (* Or *)
    zz = { (* the list of values in the link *) }; yy = Drop[zz, 1] - Drop[zz, -1]; xx = Drop[yy, 1] - Drop[yy, -1]; Join[{1}, Table[ If[ xx[[n]] > 0, 1, 0], {n, 104}]] (* Robert G. Wilson v, Jan 14 2005 *)
    Flatten[{1, (Sign[Differences[Differences[Im[ZetaZero[Range[106]]]]]] + 1)/2}] (* Mats Granvik, Jul 23 2015 *)

Extensions

Corrected and extended by Robert G. Wilson v, Jan 13 2005
Edited by M. F. Hasler, Jul 27 2015

A123504 Sequence generated from the first nontrivial zero of the Riemann zeta function.

Original entry on oeis.org

1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0
Offset: 2

Views

Author

Gary W. Adamson, Oct 01 2006

Keywords

Comments

A123505 records the lengths of runs. A123506 uses the second zero.

Examples

			a(8) = 1 since (1/8)^z = (0.353553..., angle 115.943... degrees).
		

Crossrefs

Programs

  • Mathematica
    a[n_] := Boole[Arg[1/n^ZetaZero[1]] > 0]; Array[a, 100, 2] (* Amiram Eldar, May 31 2025 *)
  • PARI
    t=1/2+solve(y=14,15,imag(zeta(1/2+y*I)))*I;
    a(n)=arg(n^-t)>0 \\ Charles R Greathouse IV, Mar 10 2016

Formula

Extract argument from (1/n)^z, z = (1/2 + i*14.1347251417...). a(n) = 1 if the argument is between 0 and 180 degrees, and = 0 if otherwise (n = 2, 3, 4, ...).

Extensions

More terms from Amiram Eldar, May 31 2025

A123505 Lengths of bit runs in A123504.

Original entry on oeis.org

1, 2, 1, 2, 2, 2, 3, 3, 5, 6, 7, 8, 11, 14, 17, 21, 26, 34, 41, 51, 65, 80, 101, 125, 157, 196, 245, 305, 381, 477, 595, 743, 927, 1159, 1448, 1807, 2258, 2819, 3521, 4397, 5492, 6859, 8565, 10698, 13361, 16685, 20839, 26026, 32503, 40593, 50697, 63315, 79074
Offset: 2

Views

Author

Gary W. Adamson, Oct 01 2006

Keywords

Comments

A123507 records the bit runs of A123506 and uses the second zero in an analogous operation.
Record the numbers of consecutive bit runs of A123504, see example.

Examples

			A123504 = 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1...; therefore the numbers of bit runs are 1, 2, 1, 2, 2, 2, 3, ...
		

Crossrefs

Programs

  • Mathematica
    Length /@ Split[Table[Boole[Arg[1/n^ZetaZero[1]] > 0], {n, 2, 10^6}]] (* Amiram Eldar, May 31 2025 *)

Extensions

More terms from Amiram Eldar, May 31 2025

A123506 Sequence generated from the second nontrivial zero of the Riemann zeta function.

Original entry on oeis.org

0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
Offset: 2

Views

Author

Gary W. Adamson, Oct 02 2006

Keywords

Comments

A123504 performs an analogous set of operations using the first nontrivial zero. A123507 records the lengths of runs in this sequence.
Let z = (1/2 + i*t), t = 21.0220396387... (the second nontrivial Riemann zeta function zero). Perform (1/n)^z, (n = 2, 3, 4, ...) extracting the argument. If the argument is between 0 and 180 degrees, a(n) = 1, otherwise a(n) = 0.

Examples

			a(7) = 1 since (1/7)^z = (0.37796447..., angle 176.201... degrees) and the argument is between 0 and 180 degrees.
		

References

  • John Derbyshire, Prime Obsession, Bernhard Riemann and the Greatest Unsolved Problem in Mathematics, Plume - a Penguin Group, NY, 2003, pp. 198-199.

Crossrefs

Programs

  • Mathematica
    a[n_] := Boole[Arg[1/n^ZetaZero[2]] > 0]; Array[a, 100, 2] (* Amiram Eldar, May 31 2025 *)

Extensions

More terms from Amiram Eldar, May 31 2025

A123507 Lengths of bit runs in A123506.

Original entry on oeis.org

1, 2, 1, 3, 1, 1, 2, 2, 3, 2, 4, 3, 5, 5, 5, 7, 8, 9, 11, 12, 14, 17, 19, 22, 26, 31, 34, 41, 47, 55, 64, 73, 86, 100, 115, 135, 156, 181, 210, 244, 283, 329, 383, 443, 516, 598, 695, 807, 936, 1088, 1263, 1467, 1703, 1978, 2297, 2666, 3097, 3595, 4176, 4848, 5630
Offset: 2

Views

Author

Gary W. Adamson, Oct 01 2006

Keywords

Comments

The sequence uses operations based on the second nontrivial Riemann zero: (1/2 + i*t), t = 21.022039639... A123504 and A123505 use the first nontrivial zero.
Record the numbers of consecutive bit runs of A123506, see example.

Examples

			a(4) = 3 since A123506 = 0, 1, 1, 0, 1, 1, 1, ...
		

References

  • John Derbyshire, Prime Obsession, Bernhard Riemann and the Greatest Unsolved Problem in Mathematics, Plume - a Penguin Group, NY, 2003, pp. 198-199.

Crossrefs

Programs

  • Mathematica
    Length /@ Split[Table[Boole[Arg[1/n^ZetaZero[2]] > 0], {n, 2, 10^6}]] (* Amiram Eldar, May 31 2025 *)

Extensions

More terms from Amiram Eldar, May 31 2025
Showing 1-6 of 6 results.