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A280876
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Palindromic primes with prime subscripts.
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1
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3, 5, 11, 191, 353, 797, 919, 11311, 12421, 13331, 16061, 18181, 31513, 32323, 34543, 34843, 36563, 37273, 70207, 72727, 77377, 78787, 1117111, 1120211, 1253521, 1257521, 1280821, 1328231, 1409041, 1456541, 1633361, 1824281, 1851581, 1903091, 1982891, 1984891, 1998991, 3002003, 3073703, 3211123, 3212123, 3252523
(list;
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refs;
listen;
history;
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internal format)
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OFFSET
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1,1
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COMMENTS
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Intersection of A002385 and A006450.
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LINKS
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Chai Wah Wu, Table of n, a(n) for n = 1..1000
Eric Weisstein's World of Mathematics, Palindromic Prime
Index entries for sequences related to palindromes
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EXAMPLE
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11311 is in the sequence because 11311 is a palindrome, 11311 is a 1367-th prime number and 1367 is prime.
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MATHEMATICA
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Select[Prime@ Prime@ Range@ 20000, PalindromeQ] (* modified by Robert G. Wilson v, Jan 09 2017 *)
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PROG
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(Python)
from itertools import chain, count, islice
from sympy import isprime, primepi
def A280876_gen(): # generator of terms
return filter(lambda n:isprime(n) and isprime(primepi(n)), chain.from_iterable(chain((int((s:=str(d))+s[-2::-1]) for d in range(10**l, 10**(l+1))), (int((s:=str(d))+s[::-1]) for d in range(10**l, 10**(l+1)))) for l in count(0)))
A280876_list = list(islice(A280876_gen(), 20)) # Chai Wah Wu, Jun 23 2022
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CROSSREFS
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Cf. A000040, A002113, A002385, A006450.
Sequence in context: A062601 A231017 A038198 * A357055 A079037 A281087
Adjacent sequences: A280873 A280874 A280875 * A280877 A280878 A280879
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KEYWORD
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nonn,base,easy
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AUTHOR
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Ilya Gutkovskiy, Jan 09 2017
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STATUS
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approved
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