A261269 Minimal prime concatenation sequence with base 2 and seed 11.

11, 111, 11101, 111011, 11101111, 111011111, 111011111001, 111011111001111, 1110111110011111, 11101111100111110101, 1110111110011111010101, 11101111100111110101010101, 11101111100111110101010101011, 1110111110011111010101010101111

Offset: 1

Author

Clark Kimberling, Sep 16 2015

Keywords

• nonn
• easy
• base

Examples

			In base 2, the least prime starting with seed 1 is 11; the least prime starting with 11 is 111; the least prime starting with 111 is 11101. Triangular format:
11
111
11101
111011
11101111
1110111111
111011111001
		

Links

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

Crossrefs

Cf. A261270.

Programs

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] (* A261269 *)
Map[FromDigits[#, b] &, s] (* A261270 *)
(* Peter J. C. Moses, Aug 06 2015 *)