A337872 - OEIS

A337872

Primes obtained by interpreting the decimal representation of a prime p in base q, where q is the prime before p.

%I #12 Sep 28 2020 22:26:04

%S 41,149,167,179,373,673,23563,38993,40591,294227,329683,643213,838139,

%T 2391491,2755393,4144913,7770163,8422571,8705449,1859356559,

%U 2207151707,2299966681,3063365713,4212265633,5728918291,6598803767,15976012001,18180161711,18819045697,19687839581,20701458763,22458791039

%N Primes obtained by interpreting the decimal representation of a prime p in base q, where q is the prime before p.

%H Robert Israel, <a href="/A337872/b337872.txt">Table of n, a(n) for n = 1..10000</a>

%e a(3)=167 is included because it is prime, and for p = 43 (prime) and q = 41 (the previous prime), 43_41 = 167.

%p R:= NULL: count:= 0:

%p p:= 11:

%p while count < 100 do

%p q:= p; p:= nextprime(p);

%p L:= convert(p, base, 10);

%p x:= add(L[i]*q^(i-1), i=1..nops(L));

%p if isprime(x) then count:= count+1; R:= R, x;

%p fi

%p od:

%p R;

%Y Cf. A337871.

%K nonn,base

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Sep 27 2020