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A355983
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Primes whose reversal is a multiple of 4.
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3
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23, 29, 61, 67, 211, 233, 239, 251, 257, 271, 277, 293, 401, 409, 421, 443, 449, 461, 463, 467, 487, 613, 617, 619, 631, 653, 659, 673, 677, 691, 809, 821, 823, 827, 829, 863, 881, 883, 887, 2111, 2113, 2129, 2131, 2137, 2141, 2143, 2153, 2161, 2179, 2309, 2311, 2333, 2339, 2341, 2347, 2351
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OFFSET
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1,1
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COMMENTS
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Equivalently, primes starting with 21, 23, 25, 27, 29, 40, 42, 44, 46, 48, 61, 63, 65, 67, 69, 80, 82, 84, 86, 88.
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LINKS
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EXAMPLE
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67 is a term since 67 is prime and 76 is divisible by 4.
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MATHEMATICA
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Select[Prime[Range[350]], Divisible[IntegerReverse[#], 4] &] (* Amiram Eldar, Jul 22 2022 *)
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PROG
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(PARI) isok(p) = isprime(p) && !(fromdigits(Vecrev(digits(p))) % 4); \\ Michel Marcus, Jul 22 2022
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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