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 1-3 of 3 results.

A016958 a(n) = (6n + 4)^2.

Original entry on oeis.org

16, 100, 256, 484, 784, 1156, 1600, 2116, 2704, 3364, 4096, 4900, 5776, 6724, 7744, 8836, 10000, 11236, 12544, 13924, 15376, 16900, 18496, 20164, 21904, 23716, 25600, 27556, 29584, 31684, 33856
Offset: 0

Views

Author

N. J. A. Sloane

Keywords

Links

Crossrefs

Cf. A016957, A086730.

Programs

Formula

a(n) = (A016957(n))^2. - Zerinvary Lajos, Jun 30 2009
Sum_{n>=0} 1/a(n) = A086730. - Amiram Eldar, Nov 17 2020

Extensions

Notation in formula cleaned up by R. J. Mathar, Aug 05 2010

A086731 Decimal expansion of sum(1/(6*m+5)^2,m=0..infinity).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Jul 31 2003

Keywords

Examples

			0.05999734755577...

References

  • L. Fejes Toth, Lagerungen in der Ebene, auf der Kugel und im Raum, 2nd. ed., Springer-Verlag, Berlin, Heidelberg 1972; see p. 213.

Crossrefs

Cf. A086722-A086730.

Programs

  • Mathematica
    Join[{0},RealDigits[1/36 PolyGamma[1,5/6],10,120][[1]]] (* Harvey P. Dale, Dec 15 2011 *)

A086729 Decimal expansion of Pi^2/72.

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Jul 31 2003

Keywords

Comments

The original name was: Decimal expansion of Sum_{m=0..infinity} 1/(6*m+3)^2.

Examples

			0.1370778389040188697...

References

  • L. Fejes Toth, Lagerungen in der Ebene, auf der Kugel und im Raum, 2nd. ed., Springer-Verlag, Berlin, Heidelberg 1972; see p. 213.

Links

Crossrefs

Cf. A086722, A086723, A086724, A086725, A086726, A086727, A086728, A086730, A086731, A111003, A353908.

Programs

Formula

Equals A111003/9. - R. J. Mathar, Dec 18 2010
From Amiram Eldar, Jul 19 2020: (Start)
Sum_{k>=0} (1/(12*k+3)^2 + 1/(12*k+9)^2).
Equals Integral_{x=1..oo} log(1 + 1/x^6)/x dx. (End)
Equals A353908/2. - Omar E. Pol, May 12 2022

Extensions

New name after R. J. Mathar's Maple program. - Omar E. Pol, May 12 2022
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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