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%I #17 Jun 23 2022 17:47:04
%S 3,5,11,191,353,797,919,11311,12421,13331,16061,18181,31513,32323,
%T 34543,34843,36563,37273,70207,72727,77377,78787,1117111,1120211,
%U 1253521,1257521,1280821,1328231,1409041,1456541,1633361,1824281,1851581,1903091,1982891,1984891,1998991,3002003,3073703,3211123,3212123,3252523
%N Palindromic primes with prime subscripts.
%C Intersection of A002385 and A006450.
%H Chai Wah Wu, <a href="/A280876/b280876.txt">Table of n, a(n) for n = 1..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PalindromicPrime.html">Palindromic Prime</a>
%H <a href="/index/Pac#palindromes">Index entries for sequences related to palindromes</a>
%e 11311 is in the sequence because 11311 is a palindrome, 11311 is a 1367-th prime number and 1367 is prime.
%t Select[Prime@ Prime@ Range@ 20000, PalindromeQ] (* modified by _Robert G. Wilson v_, Jan 09 2017 *)
%o (Python)
%o from itertools import chain, count, islice
%o from sympy import isprime, primepi
%o def A280876_gen(): # generator of terms
%o 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)))
%o A280876_list = list(islice(A280876_gen(),20)) # _Chai Wah Wu_, Jun 23 2022
%Y Cf. A000040, A002113, A002385, A006450.
%K nonn,base,easy
%O 1,1
%A _Ilya Gutkovskiy_, Jan 09 2017
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