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A085300 a(n) is the least prime x such that when reversed it is a power of prime(n). 3

%I #9 Jun 03 2016 02:41:18

%S 2,3,5,7,11,31,71,163,18258901387,90367894271,13,73,1861,344800741,

%T 34351783286302805384336021,940315563074788471,1886172359328147919771,

%U 14854831

%N a(n) is the least prime x such that when reversed it is a power of prime(n).

%C A006567 (after rearranging terms) and A002385 are subsequences. - _Chai Wah Wu_, Jun 02 2016

%H Chai Wah Wu, <a href="/A085300/b085300.txt">Table of n, a(n) for n = 1..86</a>

%e a(14)=344800741 means that 147008443=43^5=p(14)^5, where 5 is the smallest such exponent;

%e a(19) has 82 decimal digits and if reversed equals 39th power of p(19)=67.

%o (Python)

%o from sympy import prime, isprime

%o def A085300(n):

%o p = prime(n)

%o q = p

%o while True:

%o m = int(str(q)[::-1])

%o if isprime(m):

%o return(m)

%o q *= p # _Chai Wah Wu_, Jun 02 2016

%Y Cf. A085298, A057708, A058993, A056994, A059695, A003459, A007500, A055387, A061461, A068652.

%K base,nonn

%O 1,1

%A _Labos Elemer_, Jun 24 2003

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Last modified March 29 10:22 EDT 2024. Contains 371268 sequences. (Running on oeis4.)