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.

Previous Showing 11-14 of 14 results.

A360095 Decimal expansion of Sum_{p primes, p == 3 (mod 4)} log(p)/p^2.

Original entry on oeis.org

2, 1, 2, 4, 4, 4, 7, 6, 8, 9, 3, 1, 6, 6, 5, 0, 5, 7, 7, 0, 5, 0, 6, 7, 7, 9, 2, 6, 8, 2, 8, 2, 5, 2, 1, 4, 8, 7, 0, 3, 7, 3, 6, 9, 5, 8, 4, 3, 7, 6, 6, 6, 9, 7, 8, 1, 0, 4, 9, 7, 5, 3, 7, 1, 6, 7, 7, 0, 9, 5, 9, 7, 6, 0, 2, 0, 8, 1, 1, 5, 3, 5, 8, 9, 6, 1, 3, 7, 0, 5, 9, 6, 1, 4, 0, 7, 4, 3, 8, 3, 3, 7, 4, 4, 7, 3
Offset: 0

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Author

Vaclav Kotesovec, Jan 25 2023

Keywords

Examples

			0.212444768931665057705067792682825214870373695843766697810497537167709...
		

Crossrefs

Programs

  • Mathematica
    beta[s_]:= (1 - 1/2^s) * Zeta[s] / DirichletBeta[s]; Do[Print[N[-1/2*Sum[MoebiusMu[2*n + 1]/(2*n + 1) * D[Log[beta[(2*n + 1)*s]], s] /. s->2, {n, 0, m}], 120]], {m, 10, 100, 10}]

Formula

Equals A136271 - A360094 - log(2)/4.

A154928 Decimal expansion of Sum_{q in A001358} log(q)/q^2 over the semiprimes q = 4,6,9,...

Original entry on oeis.org

0, 2, 8, 3, 6, 0, 6, 8, 1, 5, 4, 0, 7, 9, 8, 0, 6, 5, 2, 2, 2, 4, 2, 5, 8, 2, 2, 2, 5, 4, 8, 2, 7, 8, 3, 3, 6, 0, 7, 9, 3, 5, 0, 5, 7, 8, 2, 3, 7, 8, 1, 4, 0, 1, 3, 4, 1, 1, 1, 1
Offset: 0

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Author

R. J. Mathar, Jan 17 2009

Keywords

Comments

Semiprime analog of A136271. The absolute value of the first derivative of the semiprime zeta function at 2.

Examples

			Equals 0.0283606815... = log(4)/16 + log(6)/36 + log(9)/81 + ....
		

Formula

Equals Sum_{j>=1} log(A001358(j))/A074985(j).

Extensions

Missing zero inserted. Artur Jasinski, Jul 29 2025

A373809 Decimal expansion of the second derivative P''(2) of the prime zeta function at 2.

Original entry on oeis.org

7, 4, 1, 5, 9, 7, 8, 5, 4, 9, 8, 2, 8, 0, 5, 0, 0, 3, 0, 2, 3, 9, 4, 0, 3, 2, 7, 5, 4, 5, 0, 3, 7, 5, 4, 1, 3, 2, 1, 6, 1, 4, 0, 5, 6, 8, 6, 9, 3, 5, 9, 6, 2, 7, 0, 1, 7, 4, 5, 8, 2, 9, 4, 3, 3, 8, 6, 5, 3, 6, 4, 5, 7, 0, 6, 8, 0, 0, 0, 0, 2, 5, 7, 1, 3, 8, 3, 3, 7, 2, 4, 3, 0, 5, 6, 2, 5, 6, 3, 5, 2, 9, 5, 8, 2
Offset: 0

Views

Author

R. J. Mathar, Aug 18 2024

Keywords

Examples

			0.74159785498280500302394032754503754132161405686935...
		

Crossrefs

Cf. A085548 (P(2)), A136271 (P'(2)).

Programs

  • Mathematica
    $MaxExtraPrecision = 200; RealDigits[N[PrimeZetaP''[2], 120]][[1]] (* Amiram Eldar, Aug 19 2024 *)

Formula

Equals Sum_{primes = 2,3,5,7,...} log(p)^2/p^2.

Extensions

More terms from Amiram Eldar, Aug 19 2024

A375509 Decimal expansion of the negated derivative P'(3/2) of the prime zeta function at 3/2.

Original entry on oeis.org

1, 2, 9, 5, 7, 1, 0, 7, 5, 4, 7, 9, 1, 6, 0, 7, 5, 5, 3, 7, 2, 2, 8, 8, 8, 3, 2, 4, 6, 4, 5, 5, 5, 7, 6, 6, 3, 4, 9, 4, 1, 6, 2, 9, 4, 6, 9, 8, 4, 5, 2, 9, 7, 5, 4, 4, 9, 6, 5, 1, 9, 7, 3, 8, 0, 1, 8, 1, 4, 4, 0, 0, 5, 2, 6, 6, 8, 1, 1, 7, 5, 7, 4, 3, 9, 6, 5, 1, 3, 4, 8, 7, 5, 5, 0, 0, 4, 4, 1, 1
Offset: 1

Views

Author

R. J. Mathar, Aug 18 2024

Keywords

Examples

			1.29571075479160755372288832464555766349416294698452...
		

Crossrefs

Cf. A338574 (P(3/2)), A136271 (P'(2)).

Programs

  • Mathematica
    $MaxExtraPrecision = 100; RealDigits[N[PrimeZetaP'[3/2], 120]][[1]] (* Amiram Eldar, Aug 19 2024 *)

Formula

P'(3/2) = -Sum_{p = 2,3,5,7,11,..} log(p)/p^(3/2) = -1.29571075479160755372...
Previous Showing 11-14 of 14 results.