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A034302 Primes which remains prime if any digit is deleted (zeros not allowed). 15
23, 37, 53, 73, 113, 131, 137, 173, 179, 197, 311, 317, 431, 617, 719, 1499, 1997, 2239, 2293, 3137, 4919, 6173, 7433, 9677, 19973, 23833, 26833, 47933, 73331, 74177, 91733, 93491, 94397, 111731, 166931, 333911, 355933, 477797, 477977 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

T. D. Noe, Table of n, a(n) for n = 1..79

StackExchange, Deleting any digit yields a prime

MATHEMATICA

rpnzQ[n_]:=Module[{idn=IntegerDigits[n]}, Count[idn, 0]==0 && And@@ PrimeQ[FromDigits/@Subsets[IntegerDigits[n], {Length[idn]-1}]]]; Select[Prime[Range[40000]], rpnzQ]  (* Harvey P. Dale, Mar 24 2011 *)

PROG

(Haskell)

import Data.List (inits, tails)

a034302 n = a034302_list !! (n-1)

a034302_list = filter f $ drop 4 a038618_list where

   f x = all (== 1) $ map (a010051 . read) $

             zipWith (++) (inits $ show x) (tail $ tails $ show x)

-- Reinhard Zumkeller, Dec 17 2011

(PARI) is(n)=my(d=digits(n), t=2^#d-1); if(vecmin(d)==0, return(0)); for(i=0, #d-1, if(!isprime(fromdigits(vecextract(d, t-2^i))), return(0))); isprime(n) \\ Charles R Greathouse IV, Jun 23 2017

CROSSREFS

Cf. A034303, A034304, A034305, A051362, A010051, A038618.

Sequence in context: A057876 A244282 A051362 * A057878 A019549 A272157

Adjacent sequences:  A034299 A034300 A034301 * A034303 A034304 A034305

KEYWORD

base,nonn,nice,changed

AUTHOR

David W. Wilson

STATUS

approved

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Last modified June 23 20:08 EDT 2017. Contains 288675 sequences.