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 1-2 of 2 results.

A102131 Iccanobirt prime indices (1 of 15): Indices of prime numbers in A102111.

Original entry on oeis.org

4, 6, 7, 19, 30, 175, 265, 591, 1124, 1369, 4359, 10935, 20422, 20559, 26993
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Comments

No more terms through 8000.
a(16) > 50000. - Robert Price, Nov 07 2018

Crossrefs

Cf. A000040, A102111, A102132-A102145.

Programs

  • Mathematica
    a[n_] := a[n] = 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

A102111(a(n)) = A102151(n).

Extensions

a(12)-a(15) from Robert Price, Nov 07 2018

A102152 Iccanobirt primes (2 of 15): Prime numbers in A102112.

Original entry on oeis.org

2, 7, 13, 167, 1843406868619, 567512739603223, 1125599723626314594798370059933052227890281327798090340341843
Offset: 1

Views

Author

Jonathan Vos Post and Ray Chandler, Dec 31 2004

Keywords

Comments

Next term is too large to include.
The next term (a(8)) has 394 digits. The term after that (a(9)) has 1063 digits, and a(10) has 2599 digits. - Harvey P. Dale, Dec 26 2022

Crossrefs

Cf. A000040, A102112, A102151-A102165.

Programs

  • Mathematica
    nxt[{a_,b_,c_}]:={b,c,a+FromDigits[Reverse[IntegerDigits[b]]]+c};Select[NestList[nxt,{0,0,1},200][[All,1]],PrimeQ] (* Harvey P. Dale, Dec 26 2022 *)

Formula

a(n) = A102112(A102132(n)).

Extensions

Offset changed to 1 by Jinyuan Wang, Aug 08 2021
Showing 1-2 of 2 results.

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

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