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 11-16 of 16 results.

A102138 Iccanobirt prime indices (8 of 15): Indices of prime numbers in A102118.

Original entry on oeis.org

4, 6, 7, 12, 25, 72, 100, 126, 167, 253, 396, 856, 1013, 1172, 1413, 2138, 23926, 28255
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Comments

No more terms through 5000.
a(19) > 50000. - Robert Price, Nov 09 2018

Crossrefs

Programs

  • Mathematica
    a[n_] := a[n] = IntegerReverse[(a[n - 1] + a[n - 2] + a[n - 3])];
    a[0] = 0; a[1] = 0; a[2] = 1;
    Select[Range[0, 5000], PrimeQ[a[#]] &] (* Robert Price, Apr 10 2020 *)

Formula

A102118(a(n)) = A102158(n).

Extensions

a(17)-a(18) from Robert Price, Nov 09 2018

A102139 Iccanobirt prime indices (9 of 15): Indices of prime numbers in A102119.

Original entry on oeis.org

4, 6, 7, 11, 15, 19, 233, 549, 1608, 4143, 4633, 9642
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Comments

No more terms through 5000.
a(13) > 50000. - Robert Price, Nov 09 2018

Crossrefs

Programs

  • Mathematica
    a[n_] := a[n] =
       IntegerReverse[(a[n - 1] + a[n - 2] + IntegerReverse[a[n - 3]])];
    a[0] = 0; a[1] = 0; a[2] = 1;
    Select[Range[0, 5000], PrimeQ[a[#]] &] (* Robert Price, Apr 10 2020 *)

Formula

A102119(a(n)) = A102159(n).

Extensions

a(12) from Robert Price, Nov 09 2018

A102140 Iccanobirt prime indices (10 of 15): Indices of prime numbers in A102120.

Original entry on oeis.org

4, 6, 7, 11, 12, 20, 25, 45, 113, 193, 1214, 1272, 2435, 4007, 12258, 12771, 14166, 27368, 29184
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Comments

No more terms through 5000.
a(20) > 50000. - Robert Price, Nov 10 2018

Crossrefs

Programs

  • Mathematica
    b[0] = b[1] = 0; b[2] = 1; b[n_] := b[n] = IntegerReverse[b[n - 1] + IntegerReverse[b[n - 2]] + b[n - 3]];
    Reap[Do[If[PrimeQ[b[n]], Print[n]; Sow[n]], {n, 5000}]][[2, 1]] (* Jean-François Alcover, Dec 15 2017 *)

Formula

A102120(a(n)) = A102160(n).

Extensions

a(15)-a(19) from Robert Price, Nov 10 2018

A102141 Iccanobirt prime indices (11 of 15): Indices of prime numbers in A102121.

Original entry on oeis.org

4, 6, 7, 15, 25, 51, 126, 171, 311, 358, 865, 1850, 3311, 4686, 7893, 8249, 17795, 27176, 48728
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Comments

No more terms through 5000.
a(20) > 50000. - Robert Price, Nov 10 2018

Crossrefs

Programs

  • Mathematica
    a[n_] := a[n] =
       IntegerReverse[a[n - 1] + IntegerReverse[a[n - 2]] + IntegerReverse[a[n - 3]]];
    a[0] = 0; a[1] = 0; a[2] = 1;
    Select[Range[0, 5000], PrimeQ[a[#]] &] (* Robert Price, Apr 10 2020 *)

Formula

A102121(a(n)) = A102161(n).

Extensions

a(15)-a(19) from Robert Price, Nov 10 2018

A102142 Iccanobirt prime indices (12 of 15): Indices of prime numbers in A102122.

Original entry on oeis.org

4, 6, 7, 12, 19, 30, 37, 67, 93, 109, 297, 341, 602, 1377, 1745, 1972, 4208, 7942, 9572, 10409, 11927, 12707, 13460, 33803
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Comments

No more terms through 5000.
a(25) > 50000. - Robert Price, Nov 10 2018

Crossrefs

Programs

  • Mathematica
    a[n_] := a[n] =
       IntegerReverse[IntegerReverse[a[n - 1]] + a[n - 2] + a[n - 3]];
    a[0] = 0; a[1] = 0; a[2] = 1;
    Select[Range[0, 5000], PrimeQ[a[#]] &] (* Robert Price, Apr 10 2020 *)

Formula

A102122(a(n)) = A102162(n).

Extensions

a(18)-a(24) from Robert Price, Nov 10 2018

A102143 Iccanobirt prime indices (13 of 15): Indices of prime numbers in A102123.

Original entry on oeis.org

4, 6, 7, 11, 55, 56, 69, 87, 109, 191, 314, 4579, 6281, 6400, 23256, 31648
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Comments

a(17) > 50000. - Robert Price, Nov 10 2018

Crossrefs

Programs

  • Mathematica
    a[n_] := a[n] =
       IntegerReverse[IntegerReverse[a[n - 1]] + a[n - 2] + IntegerReverse[a[n - 3]]];
    a[0] = 0; a[1] = 0; a[2] = 1;
    Select[Range[0, 5000], PrimeQ[a[#]] &] (* Robert Price, Apr 10 2020 *)

Formula

A102123(a(n)) = A102163(n).

Extensions

a(13)-a(16) from Robert Price, Nov 10 2018
Offset changed to 1 by Jinyuan Wang, Aug 02 2021
Previous Showing 11-16 of 16 results.