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.

User: Michel Planat

Michel Planat's wiki page.

Michel Planat has authored 17 sequences. Here are the ten most recent ones:

A197300 The Riemann primes of the theta type and index 4.

Original entry on oeis.org

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 37, 47, 59, 61, 67, 71, 89, 97, 109, 137, 139, 167, 173, 191, 223, 229, 239, 241, 269, 271, 293, 311, 331, 347, 367, 401, 431, 433, 457, 503, 509, 571, 577, 661, 709, 719, 733, 739, 797, 911, 919, 1009
Offset: 1

Author

Michel Planat, Oct 13 2011

Keywords

Comments

The sequence consists of the prime numbers p that are champions (left to right maxima) of the function |theta(p^4)-p^4|, where theta(p) is the Chebyshev theta function, theta(x) = sum_{primes p <=x } log p.

Programs

  • Perl
    use ntheory ":all"; my($max,$f)=(0); forprimes { $f=abs(chebyshev_theta($**4)-$**4); if ($f > $max) { say; $max=$f; } } 1000; # Dana Jacobsen, Dec 28 2015

Extensions

More terms from Dana Jacobsen, Dec 28 2015

A197299 The Riemann primes of the theta type and index 3.

Original entry on oeis.org

2, 3, 5, 7, 13, 17, 23, 31, 37, 41, 43, 47, 53, 59, 67, 73, 83, 89, 101, 103, 137, 163, 167, 179, 197, 211, 223, 239, 251, 277, 331, 379, 397, 431, 463, 467, 521, 577, 593, 601, 613, 617, 719, 809, 881, 919, 967, 1091, 1123, 1129, 1237, 1249, 1289
Offset: 1

Author

Michel Planat, Oct 13 2011

Keywords

References

  • The sequence consists of the prime numbers p that are champions (left to right maxima) of the function |theta(p^3)-p^3|, where theta(p) is the Chebyshev theta function.

Crossrefs

Programs

  • Perl
    use ntheory ":all"; my($max,$f)=(0); forprimes { $f=abs(chebyshev_theta($**3)-$**3); if ($f > $max) { say; $max=$f; } } 1000; # Dana Jacobsen, Dec 28 2015

Extensions

More terms from Dana Jacobsen, Dec 28 2015

A197298 The Riemann primes of the theta type and index 2.

Original entry on oeis.org

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 43, 47, 59, 73, 97, 107, 109, 139, 179, 233, 263, 277, 283, 337, 347, 409, 419, 547, 643, 683, 809, 811, 821, 823, 863, 983, 991, 997, 1031, 1193
Offset: 1

Author

Michel Planat, Oct 13 2011

Keywords

Comments

The sequence consists of the prime numbers p that are champions (left to right maxima) of the function |theta(p^2)-p^2|, where theta(p) is the Chebyshev theta function.

Crossrefs

Programs

  • Perl
    use ntheory ":all"; my($max,$f)=(0); forprimes { $f=abs(chebyshev_theta($**2)-$**2); if ($f > $max) { say; $max=$f; } } 10000; # Dana Jacobsen, Dec 29 2015

A197297 The Riemann primes of the theta type and index 1.

Original entry on oeis.org

2, 5, 7, 11, 17, 29, 37, 41, 53, 59, 97, 127, 137, 149, 191, 223, 307, 331, 337, 347, 419, 541, 557, 809, 967, 1009, 1213, 1277, 1399, 1409, 1423, 1973, 2203, 2237, 2591, 2609, 2617, 2633, 2647, 2657, 3163, 3299, 4861, 4871, 4889, 4903, 4931, 5381, 7411
Offset: 1

Author

Michel Planat, Oct 13 2011

Keywords

Comments

The sequence consists of the prime numbers p that are champions (left to right maxima) of the function |theta(p)-p|, where theta(p) is the Chebyshev theta function.

Crossrefs

Equivalent sequences for other indices: A197298(2), A197299(3), A197300(4).

Programs

  • Perl
    use ntheory ":all"; my($max,$f)=(0); forprimes { $f=abs(chebyshev_theta($)-$); if ($f > $max) { say; $max=$f; } } 10000; # Dana Jacobsen, Dec 29 2015

A197188 The Riemann primes of the psi type and index 4.

Original entry on oeis.org

2, 5, 7, 11, 13, 17, 31, 41, 43, 71, 89, 103, 109, 139, 173, 191, 197, 241, 281, 317, 443, 487, 569, 577, 701, 761, 797, 919, 1009
Offset: 1

Author

Michel Planat, Oct 11 2011

Keywords

References

  • The sequence consists of the prime numbers p that are champions (left to right maxima) of the function |psi(p^4)-p^4|, where psi(p) is the Chebyshev psi function.

Crossrefs

Programs

  • Perl
    use ntheory ":all"; my($max,$f)=(0); forprimes { $f=abs(chebyshev_psi($**4)-$**4); if ($f > $max) { say; $max=$f; } } 1000; # Dana Jacobsen, Dec 28 2015

Extensions

More terms from Dana Jacobsen, Dec 28 2015

A197187 The Riemann primes of the psi type and index 3.

Original entry on oeis.org

2, 3, 5, 7, 11, 13, 17, 29, 59, 67, 97, 103, 149, 151, 233, 251, 277, 311, 313, 479, 643, 719, 919, 967, 1039, 1373, 1489, 1553, 1847, 1973, 1979, 2663, 2953, 3323, 3677, 3691, 4651, 4663, 4789
Offset: 1

Author

Michel Planat, Oct 11 2011

Keywords

Comments

The sequence consists of the prime numbers p that are champions (left to right maxima) of the function |psi(p^3)-p^3|, where psi(p) is the Chebyshev psi function.

Crossrefs

Programs

  • Mathematica
    ChebyshevPsi[n_] := Range[n] // MangoldtLambda // Total;
    Reap[For[max=0; p=2, p < 1000, p = NextPrime[p], f = Abs[ChebyshevPsi[p^3] - p^3]; If[f > max, max = f; Print[p]; Sow[p]]]][[2, 1]] (* Jean-François Alcover, Dec 03 2018 *)
  • Perl
    use ntheory ":all"; my($max,$f)=(0); forprimes { $f=abs(chebyshev_psi($**3)-$**3); if ($f > $max) { say; $max=$f; } } 1000; # Dana Jacobsen, Dec 28 2015

Extensions

More terms from Dana Jacobsen, Dec 28 2015

A197186 The Riemann primes of the psi type and index 2.

Original entry on oeis.org

2, 17, 31, 41, 53, 101, 109, 127, 139, 179, 397, 419, 547, 787, 997, 1031, 1229, 1801, 1811, 2099, 2237, 2417, 2423, 2657, 3163, 3203, 3517, 3581, 3583, 3931, 4241, 5503, 5507, 5557, 6079, 8087, 8719, 10433, 10487, 13399, 13411, 19309, 22303, 22307, 22613
Offset: 1

Author

Michel Planat, Oct 11 2011

Keywords

Comments

The sequence consists of the prime numbers p that are champions (left to right maxima) of the function |psi(p^2)-p^2|, where psi(p) is the Chebyshev psi function.

Crossrefs

Programs

  • Mathematica
    ChebyshevPsi[n_] := Range[n] // MangoldtLambda // Total;
    Reap[For[max=0; p=2, p < 2000, p = NextPrime[p], f = Abs[ChebyshevPsi[p^2] - p^2]; If[f > max, max = f; Print[p]; Sow[p]]]][[2, 1]] (* Jean-François Alcover, Dec 03 2018 *)
  • Perl
    use ntheory ":all"; my($max,$f)=(0); forprimes { $f=abs(chebyshev_psi($**2)-$**2); if ($f > $max) { say; $max=$f; } } 10000; # Dana Jacobsen, Dec 29 2015

Extensions

More terms from Dana Jacobsen, Dec 29 2015

A197185 The Riemann primes of the psi type and index 1.

Original entry on oeis.org

2, 59, 73, 97, 109, 113, 199, 283, 463, 467, 661, 1103, 1109, 1123, 1129, 1321, 1327, 1423, 2657, 2803, 2861, 3299, 5381, 5881, 6373, 6379, 9859, 9931, 9949, 10337, 10343, 11777, 19181, 19207, 19373, 24107, 24109, 24113, 24121, 24137, 42751, 42793, 42797
Offset: 1

Author

Michel Planat, Oct 11 2011

Keywords

Comments

The sequence consists of the prime numbers p that are champions (left to right maxima) of the function |psi(p)-p|, where psi(p) is the Chebyshev psi function.

Crossrefs

Programs

  • Mathematica
    ChebyshevPsi[n_] := Range[n] // MangoldtLambda // Total;
    Reap[For[max=0; p=2, p<50000, p = NextPrime[p], f = Abs[ChebyshevPsi[p]-p]; If[f > max, max = f; Print[p]; Sow[p]]]][[2, 1]] (* Jean-François Alcover, Dec 03 2018 *)
  • Perl
    use ntheory ":all"; my($max,$f)=(0); forprimes { $f=abs(chebyshev_psi($)-$); if ($f > $max) { say; $max=$f; } } 10000; # Dana Jacobsen, Dec 29 2015

A196675 The n-th Chebyshev primes that are equal to the 2n-th primes.

Original entry on oeis.org

164051, 231299, 255919, 274177, 343517, 447827, 450451, 528167, 587519, 847607, 1209469
Offset: 1

Author

Michel Planat, Oct 06 2011

Keywords

Comments

The Chebyshev primes (of index 1) are such odd primes that satisfy li[psi(p)]-li[psi(p-1)]<1 (sequence A196667), where li(x) is the logarithmic integral and psi(x) is the Chebyshev's psi function.
The present sequence lists the n-th Chebyshev primes that are equal to the 2n-th primes.
See A196674 for the number n at the zeros of the function a(n)-p_{2n}, where a(n) is the n-th Chebyshev prime and p_{2n} the 2n-th prime.

Crossrefs

Cf. A196674 (number n at the zeros of the function a(n)-p_{2n}, where a(n) is the n-th Chebyshev prime and p_{2n} the 2n-th prime).

A196674 Numbers n such that c(n) = p_{2n}, where c(n) is the n-th Chebyshev prime and p_{2n} the 2n-th prime.

Original entry on oeis.org

510, 10271, 11259, 11987, 14730, 18772, 18884, 21845, 24083, 33723, 46789
Offset: 1

Author

Michel Planat, Oct 05 2011

Keywords

Comments

The Chebyshev primes (of index 1) are such odd primes that satisfy li[psi(p)]-li[psi(p-1)]<1 (sequence A196667), where li(x) is the logarithmic integral and psi(x) is the Chebyshev's psi function.
THe present sequence lists the zeros of the function c(n)-p_{2n}, where c(n) is the n-th Chebyshev prime and p_{2n} the 2n-th prime.
See A196675 for the Chebyshev primes satisfying a(n)=p_{2n}.