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.

A105731 Odd numbers k such that A105658(k) != k.

Original entry on oeis.org

13, 17, 23, 25, 37, 41, 43, 47, 49, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 75, 77, 81, 83, 85, 97, 99, 103, 107, 111, 117, 121, 123, 125, 127, 129, 131, 137, 139, 143, 145, 149, 151, 153, 157, 159, 161, 163, 169, 173, 177, 179, 181, 183, 189, 191, 193, 195, 197
Offset: 1

Views

Author

Jess E. Boling (tdbpeekitup(AT)yahoo.com) and Robert G. Wilson v, Apr 18 2005

Keywords

Crossrefs

Cf. A105658, A105732, A105733, A105769.

Programs

  • Mathematica
    f[n_] := f[n] = Product[i^i, {i, n}]/Denominator[ Sum[j(j + 1)/2/(Product[j!/k!, {k, 0, j - 1}]), {j, n}]]; Select[ Range[1, 200, 2], f[ # ] != # &]

A105732 Even numbers k such that A105658(k) != k/2.

Original entry on oeis.org

16, 24, 26, 32, 40, 42, 44, 50, 54, 56, 58, 64, 84, 86, 96, 100, 102, 104, 106, 108, 110, 124, 128, 132, 136, 140, 144, 146, 148, 152, 156, 162, 164, 168, 170, 172, 174, 180, 182, 184, 186, 188, 192, 198, 204, 206, 212, 214, 224, 226, 228, 234, 236, 240, 242
Offset: 1

Views

Author

Jess E. Boling (tdbpeekitup(AT)yahoo.com) and Robert G. Wilson v, Apr 18 2005

Keywords

Crossrefs

Cf. A105658, A105731, A105733, A105769.

Programs

  • Mathematica
    f[n_] := f[n] = Product[i^i, {i, n}]/Denominator[Sum[j(j + 1)/2/(Product[j!/k!, {k, 0, j - 1}]), {j, n}]]; Select[ Range[2, 242, 2], 2f[ # ] != # &]

A105733 Numbers k such that A105658(2k-1) != 2k-1 and A105658(2k) != k.

Original entry on oeis.org

12, 13, 21, 22, 25, 27, 28, 29, 32, 42, 43, 50, 52, 54, 62, 64, 66, 70, 72, 73, 76, 81, 82, 85, 87, 90, 91, 92, 96, 99, 102, 103, 106, 112, 117, 120, 122, 123, 126, 129, 131, 132, 135, 140, 142, 144, 147, 152, 154, 155, 158, 159, 162, 169
Offset: 1

Views

Author

Jess E. Boling (tdbpeekitup(AT)yahoo.com) and Robert G. Wilson v, Apr 18 2005

Keywords

Crossrefs

Cf. A105658, A105731, A105732, A105769.

Programs

  • Mathematica
    f[n_] := f[n] = Product[i^i, {i, n}]/Denominator[Sum[j(j + 1)/2/(Product[j!/k!, {k, 0, j - 1}]), {j, n}]]; Select[ Range[125], f[2# - 1] != 2# - 1 && f[2# ] != # &]
Showing 1-3 of 3 results.

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

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