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A134809 Cyclops primes. 23
101, 103, 107, 109, 307, 401, 409, 503, 509, 601, 607, 701, 709, 809, 907, 11027, 11047, 11057, 11059, 11069, 11071, 11083, 11087, 11093, 12011, 12037, 12041, 12043, 12049, 12071, 12073, 12097, 13033, 13037, 13043, 13049, 13063 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Cyclops numbers that are prime numbers: primes with an odd number of digits with middle digit 0 that have only one digit 0.

The only known Fibonacci number in this sequence is 99194853094755497 (see A005478 and A182809).

The only known Lucas number in this sequence is 688846502588399 (see A005479 and A182811).

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..10000

G. L. Honaker, Jr. and Chris K. Caldwell, Prime Curios! 688846502588399

G. L. Honaker, Jr. and Chris K. Caldwell, Prime Curios! 99194853094755497

MATHEMATICA

(* First run the program given for A134808 *) Select[Prime[Range[2000]], cyclopsQ] (* Alonso del Arte, Dec 16 2010 *)

cycQ[n_]:=Module[{idn=IntegerDigits[n], len}, len=Length[idn]; OddQ[len] && Count[idn, 0] == 1 && idn[[(len+1)/2]]==0]; Select[Flatten[Table[Prime[ Range[ PrimePi[10^(2n)+1], PrimePi[10^(2n+1)]]], {n, 2}]], cycQ] (* Harvey P. Dale, Jun 20 2014 *)

PROG

(Python) # cyclops() in A134808

from sympy import isprime

print([c for c in cyclops(upto=13063) if isprime(c)]) # Michael S. Branicky, Jan 05 2021

CROSSREFS

Intersection of prime numbers A000040 and cyclops numbers A134808.

Cf. A005478, A005479, A056709, A069675, A182809, A182811.

Sequence in context: A243825 A345728 A309488 * A256186 A119680 A329737

Adjacent sequences:  A134806 A134807 A134808 * A134810 A134811 A134812

KEYWORD

nonn,base

AUTHOR

Omar E. Pol, Nov 25 2007

EXTENSIONS

Links added by Omar E. Pol, Mar 25 2011

STATUS

approved

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Last modified January 26 22:05 EST 2022. Contains 350601 sequences. (Running on oeis4.)