login
Primes p such that p divides the (right) concatenation of all numbers from 1 to p written in base 10 (most significant digit on left).
0

%I #18 Feb 16 2021 00:59:47

%S 2,3,5,8167,371321

%N Primes p such that p divides the (right) concatenation of all numbers from 1 to p written in base 10 (most significant digit on left).

%C Right concatenation, normal order.

%C Primes in A029455. - _Derek Orr_, Oct 04 2014

%H Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_190.htm">Puzzle 190. A follow up for the puzzle 188</a>, The Prime Puzzles & Problems Connection.

%e p=17 is not a term since 1234567891011121314151617 is not divisible by 17.

%o (PARI) p=""; n=1; while(n<10^4, p=concat(p,Str(n)); if(eval(p)%n==0&&isprime(n), print1(n,", ")); n++) \\ _Derek Orr_, Oct 04 2014

%Y Cf. A029447-A029542, A061931-A061978.

%K base,more,nonn

%O 1,1

%A _Jeff Heleen_, Aug 07 2002

%E Another term from _Jeff Heleen_, Oct 11 2009