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A100580 Palindromic primes containing digits 0 and 1 only. (Palindromic terms in A020449.) 4
11, 101, 100111001, 110111011, 111010111, 1100011100011, 1100101010011, 1101010101011, 1110110110111, 1110111110111, 100110101011001, 101000010000101, 101011000110101, 101110000011101, 110011101110011 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Jon E. Schoenfield, Table of n, a(n) for n = 1..15185 (all terms < 10^38; terms 1..200 from T. D. Noe, 201..2385 from Chai Wah Wu)
EXAMPLE
a(3) = 100111001 because 100111001 is the third palindromic prime composed only of 1's and 0's.
MATHEMATICA
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 *)
Select[FromDigits/@Tuples[{0, 1}, 15], PalindromeQ[#]&&PrimeQ[#]&] (* Harvey P. Dale, Jan 18 2023 *)
PROG
(Python)
from sympy import isprime
A100580_list = [11]
for i in range(2, 2**16):
....s = format(i, 'b')
....x = int(s+s[-2::-1])
....if isprime(x):
........A100580_list.append(x) # Chai Wah Wu, Jan 06 2015
CROSSREFS
Sequence in context: A358198 A247863 A180280 * A253631 A087744 A054421
KEYWORD
base,nonn
AUTHOR
Chuck Seggelin (seqfan(AT)plastereddragon.com), Nov 29 2004
STATUS
approved

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Last modified April 25 03:15 EDT 2024. Contains 371964 sequences. (Running on oeis4.)