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A261269 Minimal prime concatenation sequence with base 2 and seed 11. 3
11, 111, 11101, 111011, 11101111, 111011111, 111011111001, 111011111001111, 1110111110011111, 11101111100111110101, 1110111110011111010101, 11101111100111110101010101, 11101111100111110101010101011, 1110111110011111010101010101111 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

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

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 *)

CROSSREFS

Cf. A261270.

Sequence in context: A097177 A136982 A083441 * A031974 A117293 A015468

Adjacent sequences:  A261266 A261267 A261268 * A261270 A261271 A261272

KEYWORD

nonn,easy,base,changed

AUTHOR

Clark Kimberling, Sep 16 2015

STATUS

approved

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Last modified October 1 07:48 EDT 2020. Contains 337442 sequences. (Running on oeis4.)