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.

A368159 The n-th term in the trajectory of the n-th prime P under the 'Px+1' map.

Original entry on oeis.org

2, 10, 13, 5, 336, 111, 19, 215, 1404, 537, 318, 19, 1, 1, 12, 19, 1, 41231, 103, 18, 1, 10, 42, 3120474, 32580, 17, 26, 351348, 260402, 38082, 128, 60457, 138, 140, 547278, 6869, 1, 164, 21, 87, 90, 16245, 12, 194, 33, 90645, 106, 224, 1, 230, 1, 60, 121, 1
Offset: 1

Views

Author

Alois P. Heinz, Dec 13 2023

Keywords

Comments

See A057684 for definition.

Examples

			For n= 4: prime(4)  =  7 ->   50 ->  25 ->   5  = a(4).
For n= 5: prime(5)  = 11 ->  122 ->  61 -> 672 -> 336  = a(5).
For n= 6: prime(6)  = 13 ->  170 ->  85 ->  17 -> 222 -> 111  = a(6).
For n=13: prime(13) = 41 -> 1682 -> 841 ->  29 ->   1 ->  42 ->
                      21 ->    7 ->   1 ->  42 ->  21 ->   7 -> 1 = a(13).
		

Crossrefs

Main diagonal of A368085.

Programs

  • Mathematica
    Px1[p_, n_]:=Catch[For[i=1, iA368159[n_]:=Nest[Px1[Prime[n], #]&, Prime[n],n-1];
    Array[A368159,100] (* Paolo Xausa, Dec 14 2023 *)

Formula

a(n) = A368085(n,n).