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A100580 Palindromic primes containing digits 0 and 1 only. (Palindromic terms in A020449.)

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%I A100580 #25 Mar 23 2025 18:40:30
%S A100580 11,101,100111001,110111011,111010111,1100011100011,1100101010011,
%T A100580 1101010101011,1110110110111,1110111110111,100110101011001,
%U A100580 101000010000101,101011000110101,101110000011101,110011101110011
%N A100580 Palindromic primes containing digits 0 and 1 only. (Palindromic terms in A020449.)
%H A100580 Jon E. Schoenfield, <a href="/A100580/b100580.txt">Table of n, a(n) for n = 1..15185</a> (all terms < 10^38; terms 1..200 from T. D. Noe, 201..2385 from Chai Wah Wu)
%e A100580 a(3) = 100111001 because 100111001 is the third palindromic prime composed only of 1's and 0's.
%t A100580 PalQ[n_]:=FromDigits[Reverse@IntegerDigits[n]]==n; DeleteDuplicates[Flatten[Table[Select[FromDigits /@ Tuples[{0,1},n],PrimeQ[#]&&PalQ[#] &],{n,15}]]] (* _Jayanta Basu_, May 11 2013 *)
%t A100580 Select[FromDigits/@Tuples[{0,1},15],PalindromeQ[#]&&PrimeQ[#]&] (* _Harvey P. Dale_, Jan 18 2023 *)
%o A100580 (Python)
%o A100580 from sympy import isprime
%o A100580 A100580_list = [11]
%o A100580 for i in range(2, 2**16):
%o A100580     s = format(i, 'b')
%o A100580     x = int(s+s[-2::-1])
%o A100580     if isprime(x):
%o A100580         A100580_list.append(x) # _Chai Wah Wu_, Jan 06 2015
%Y A100580 Cf. A020449, A002385, A000040, A002113.
%K A100580 base,nonn
%O A100580 1,1
%A A100580 Chuck Seggelin (seqfan(AT)plastereddragon.com), Nov 29 2004