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A072384
Primes which can be represented as the sum of a cube and its reverse.
2
2, 727, 79697, 85147, 100699, 3946493, 9715169, 10301029, 11592961, 11851481, 13888793, 13913093, 17746387, 125000521, 176232571, 358030753, 417302813, 433748423, 726463627, 810090007, 817807817, 832595227, 854121557, 875444677
OFFSET
1,1
LINKS
EXAMPLE
727 is a term because it is prime and it is the sum of cube 512 and its reverse 215.
MATHEMATICA
Select[#+IntegerReverse[#]&/@(Range[1000]^3), PrimeQ]//Union (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Sep 21 2016 *)
PROG
(Python)
from sympy import isprime
def rev(n): return int(str(n)[::-1])
def aupto(lim):
c = [p**3 for p in range(1, int(lim**(1/3))+2)]
s = set(ara for ara in (a + rev(a) for a in c) if ara <= lim)
return sorted(filter(isprime, s))
print(aupto(10**9)) # Michael S. Branicky, Jun 26 2021
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Jul 20 2002
STATUS
approved