A261200 Minimal prime concatenation sequence with base 2 and seed 1.

1, 10, 101, 1011, 10111, 101111, 10111111, 101111111, 101111111011, 10111111101101, 101111111011010011, 10111111101101001101111, 10111111101101001101111101, 1011111110110100110111110101, 101111111011010011011111010111, 1011111110110100110111110101111

Offset

1,2

Links

Clark Kimberling, Table of n, a(n) for n = 1..500

Example

In base 2, the least prime starting with seed 1 is 10; the least prime starting with 10 is 101; the least prime starting with 101 is 1011. Triangular format:
1
10
101
1011
10111
101111
10111111
101111111
101111111011

Mathematica

b = 2; s = {{1}};
Do[NestWhile[# + 1 &, 0, ! (PrimeQ[FromDigits[tmp = Join[Last[s], (nn = #; IntegerDigits[nn - Sum[b^n, {n, l = NestWhile[# + 1 &, 1, ! (nn - (Sum[b^n, {n, #}]) < 0) &] - 1}], b, l + 1])], b]]) &];
AppendTo[s, tmp], {30}]; Map[FromDigits, s]
Map[FromDigits, s] (* A261200 *)
Map[FromDigits[#, b] &, s] (* A261201 *)
(* Peter J. C. Moses, Aug 06 2015 *)

Crossrefs

A055011, A261200 and A261201 are all essentially the same sequence.

Sequence in context: A190480 A267623 A283508 * A175541 A180175 A267526

Adjacent sequences: A261197 A261198 A261199 * A261201 A261202 A261203

Keyword

nonn,easy,base

Author

Clark Kimberling, Sep 16 2015

Status

approved