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A217387 Emirps (A006567) whose difference with the reversal is a perfect cube. 3
1523, 3251, 7529, 9257, 154747, 165857, 171467, 174767, 312509, 322519, 373669, 747451, 758561, 764171, 767471, 905213, 915223, 966373, 1000033, 1020233, 1077733, 1078733, 1083833, 1099933, 1165643, 1173743, 1175743 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The differences are multiples of 1728.

LINKS

Antonio Roldán, Table of n, a(n) for n = 1 to 40

EXAMPLE

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

PROG

(PARI) isinteger(n)=(n==truncate(n))

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

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) }

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

CROSSREFS

Sequence in context: A087867 A073104 A031537 * A031717 A236880 A226700

Adjacent sequences:  A217384 A217385 A217386 * A217388 A217389 A217390

KEYWORD

nonn,base

AUTHOR

Antonio Roldán, Oct 02 2012

STATUS

approved

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Last modified January 21 13:38 EST 2018. Contains 297994 sequences.