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A329737 Cyclops primes that remain prime after being "blinded". 2
101, 103, 107, 109, 307, 401, 503, 509, 601, 607, 701, 709, 809, 907, 11071, 11087, 11093, 12037, 12049, 12097, 13099, 14029, 14033, 14051, 14071, 14081, 14083, 14087, 15031, 15053, 15083, 16057, 16063, 16067, 16069, 16097, 17021, 17033, 17041, 17047, 17053 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are 14 of these primes with 3 digits and 302 with 5 digits.

LINKS

Rodolfo Ruiz-Huidobro, Table of n, a(n) for n = 1..3194

EXAMPLE

The first term, a(1), is 101 because if you remove the "cyclops' eye" it remains a prime (11) and because 101 is the 1st cyclops prime.

307 is a term because when you remove the "0" it remains a prime: 37.

PROG

(MAGMA) a:=[]; f:=func<n|IsPrime(n) and IsOdd(#a) and a[(#a+1) div 2] eq 0 and  not 0 in a[1..(#a-1) div 2] cat a[(#a+3) div 2..#a] where a is Intseq(n)>; g:=func<n|Seqint(a[1..(#a-1) div 2] cat a[(#a+3) div 2..#a]) where a is Intseq(n)>; for n in [1..20000] do if f(n) and IsPrime(g(n)) then Append(~a, n); end if; end for; a; // Marius A. Burtea, Nov 20 2019

CROSSREFS

Intersection of A256186 and A134809.

Sequence in context: A134809 A256186 A119680 * A166571 A201965 A318157

Adjacent sequences:  A329734 A329735 A329736 * A329738 A329739 A329740

KEYWORD

nonn,base,easy

AUTHOR

Rodolfo Ruiz-Huidobro, Nov 20 2019

STATUS

approved

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Last modified September 24 17:09 EDT 2020. Contains 337321 sequences. (Running on oeis4.)