A059695 Primes p such that p^2 reversed is also prime.
19, 37, 41, 89, 97, 139, 193, 271, 277, 281, 313, 331, 353, 373, 383, 397, 401, 421, 439, 443, 557, 587, 853, 971, 991, 1039, 1063, 1109, 1129, 1153, 1171, 1181, 1249, 1277, 1289, 1297, 1303, 1307, 1319, 1399, 1409, 1753, 1789, 1823, 1847, 1973
Offset: 1
Links
- T. D. Noe, Table of n, a(n) for n = 1..1000
Crossrefs
Programs
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Magma
[p: p in PrimesUpTo(2000) | IsPrime(Seqint(Reverse(Intseq(p^2))))]; // Vincenzo Librandi, Apr 12 2013
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Mathematica
Select[ Range[ 2500 ], PrimeQ[ # ] && PrimeQ[ ToExpression[ StringReverse[ ToString[ #^2 ] ] ] ] & ]
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PARI
select(p->isprime(fromdigits(Vecrev(digits(p^2)))), primes(1000)) \\ Mohammed Yaseen, Dec 31 2021
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Python
from sympy import isprime, primerange def ok(p): return isprime(int(str(p**2)[::-1])) print([p for p in primerange(1, 2000) if ok(p)]) # Michael S. Branicky, Dec 27 2021