Problems & Puzzles: Puzzles

Puzzle 578.- The smallest prime concatenating the first k primes

Here I ask for the smalllest prime concatenating the first k primes:

Here are the smallest prime up to k=6

k smallest prime

1

2

2

23

3

523

4

2357

5

112573

6

11132357

Q1. Can you extend this table?

Q2. For a similar but non equal question see A083427. Can you extend this other table?


Wow! This became a very popular puzzle!

Contributions came from: Jean Brette, Torbjörn Alm, Robert D. Mohr, Jan van Delden, Farid Liam, Seiji Tomita, J-C Rosa, Emmanuel Vantieghem, Hakan Summakoglu, Farideh Firoozbalht & J. K. Andersen.

***

For Q1 here are the solutions & Puzzlers involved.

Every puzzlers is named until his last correct entry, no matter if after his first mistake he sent other correct entries.

k  & smallest prime Puzzlers
7 1113257317 TA, FL, JC, EV, HS, FF, JKA, RM, JVD
8 111317193257 TA, FL, JC, EV, HS, FF, JKA, RM, JVD
9 11131719223357 TA, FL, JC, EV, HS, FF, JKA, RM, JVD
10 none  
11 111317192232935317 TA, FL, JC, HS, FF, JKA, RM, JVD
12 11131719223293157373 FL, HS, FF, JKA, RM, JVD
13 1113171922329313377541 FL, HS, FF, JKA, RM, JVD
14 111317192232931337415743 FL, HS, FF, JKA, RM, JVD
15 11131719223293133741474357 HS, FF, JKA, RM, JVD
16 none  
17 111317192232931337414355975347 HS, FF, JKA, RM, JVD
18 none  
19 1113171922329313374143475357596167 HS, FF, JKA, RM, JVD
20 none  
21 11131719223293133741434753559677376171 HS, JKA, RM, JVD
22 1113171922329313374143475355961677973771 HS, JKA, RM, JVD
23 111317192232931337414347535596167718373779 HS, JKA, RM, JVD
24 none  
25 1113171922329313374143475355961677173779898397 HS, JKA, RM, JVD
26 none  
27 1011031113171922329313374143475355961677173837899779 JKA, JVD
28 none  
29 1011031071091113171922329313374143475355961677173797798983 JKA, JVD

For Q2:

Primes Puzzlers
n=9       11131719223357 HS, FF, EV
n=10     1113171922335437 HS, FF, EV
n=11     111317192232934157 HS, FF, EV
n=12     11131719223293135773 HS, FF
n=13     1113171922329313375759 HS, FF
n=14     111317192232931337415743 HS, FF
n=15     11131719223293133741435717 HS, FF
n=16     1113171922329313374143477357 HS, FF
n=17     111317192232931337414347559783 HS
n=18     11131719223293133741434753578371 HS
n=19     1113171922329313374143475355961789 HS
n=20     111317192232931337414347535596173797 HS
n=21     11131719223293133741434753559616771783 HS
n=22     1113171922329313374143475355961677197779 HS
n=23     111317192232931337414347535596167717389779 HS
n=24     11131719223293133741434753559616771797389977 HS
n=25     1113171922329313374143475355961677173779898397 HS

 


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