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A160561

Cyclops primes with circular digits {0,6,8,9}.

809, 66089, 68099, 86069, 88069, 89069, 99089, 6680689, 6680699, 6680969, 6690689, 6690899, 6690989, 6860869, 6860989, 6860999, 6890699, 6890969, 6960869, 6980669, 6980899, 6980969, 6990889, 8660689, 8660699, 8660969

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OFFSET

1,1

COMMENTS

The sequence is probably infinite.

The sequence A134809 restricted to cases with digits 6, 8 or 9 (see A001743) at the off-center positions.

Primes in A274765. - Omar E. Pol, Jul 06 2016

Each term is equal to 9 mod 10. - Harvey P. Dale, Feb 02 2021

LINKS

Kenny Lau, Table of n, a(n) for n = 1..20000

MATHEMATICA

Select[Prime@ Range[10^6], And[OddQ@ Length@ #, Times @@ Boole@ Map[MemberQ[{0, 6, 8, 9}, #] &, Union@ #] == 1, Part[#, Ceiling[Length[#]/2]] == 0, Count[#, 0] == 1] &@ IntegerDigits@ # &] (* Michael De Vlieger, Jul 05 2016 *)

Table[Select[FromDigits/@(Flatten[Join[{Take[#, Length[#]/2], 0, Take[#, -Length[#]/2]}]]&/@Tuples[{6, 8, 9}, n]), PrimeQ], {n, 2, 6, 2}]//Flatten (* Harvey P. Dale, Feb 02 2021 *)

CROSSREFS

Intersection of A000040 (primes), A001743 (numbers with circular digits) and A134808 (cyclops numbers).

Also intersection of A043580 (primes with circular digits) and A134809 (cyclops primes).

Cf. A134808, A134809, A153807, A156200, A274765.

Sequence in context: A031599 A265984 A332848 * A346716 A156404 A381893

Adjacent sequences: A160558 A160559 A160560 * A160562 A160563 A160564

KEYWORD

nonn,base

AUTHOR

Ki Punches, May 19 2009

EXTENSIONS

Edited and corrected by Ray Chandler and R. J. Mathar, May 20 2009

Definition simplified by Omar E. Pol, Jun 05 2009

STATUS

approved

URL: https://oeis.org/A160561

⇱ A160561 - OEIS