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A134809 Cyclops primes. 18
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

FORMULA

Intersection of prime numbers A000040 and cyclops numbers A134808.

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 *)

CROSSREFS

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

Sequence in context: A183087 A056709 A243825 * A256186 A119680 A166571

Adjacent sequences:  A134806 A134807 A134808 * A134810 A134811 A134812

KEYWORD

nonn,base,less

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 August 22 12:54 EDT 2017. Contains 290948 sequences.