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A100580 Palindromic primes containing digits 0 and 1 only. (Palindromic terms in A020449.) 3
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 *)

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

Cf. A020449, A002385, A000040, A002113.

Sequence in context: A001387 A247863 A180280 * A253631 A087744 A054421

Adjacent sequences:  A100577 A100578 A100579 * A100581 A100582 A100583

KEYWORD

base,nonn

AUTHOR

Chuck Seggelin (seqfan(AT)plastereddragon.com), Nov 29 2004

STATUS

approved

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Last modified July 4 05:54 EDT 2020. Contains 335444 sequences. (Running on oeis4.)