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A217387 Emirps (A006567) whose difference with the reversal is a perfect cube. 3

%I

%S 1523,3251,7529,9257,154747,165857,171467,174767,312509,322519,373669,

%T 747451,758561,764171,767471,905213,915223,966373,1000033,1020233,

%U 1077733,1078733,1083833,1099933,1165643,1173743,1175743

%N Emirps (A006567) whose difference with the reversal is a perfect cube.

%C The differences are multiples of 1728.

%H Antonio Roldán, <a href="/A217387/b217387.txt">Table of n, a(n) for n = 1 to 40</a>

%e 905213 is prime, 312509 is prime. 905213 - 312509 = 592704 = 84^3.

%o (PARI) isinteger(n)=(n==truncate(n))

%o reverse(n)=eval(concat(Vecrev(Str(n))))

%o iscube(n)= { local(f,m,p=0); if(n==1,p=1, f=factor(n); m=gcd(f[, 2]); if(isinteger(m/3),p=1));return(p) }

%o {for(i=2,10^7,p=reverse(i);if(isprime(i)&&isprime(p)&&iscube(abs(i-p)),print1(i," ")))} /* Antonio Roldán, Dec 19 2012 */

%K nonn,base

%O 1,1

%A _Antonio Roldán_, Oct 02 2012

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Last modified October 24 20:35 EDT 2021. Contains 348233 sequences. (Running on oeis4.)