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A305352 Deletable primes (A080608) under the stricter rule that leading zeros are disallowed. 3
2, 3, 5, 7, 13, 17, 23, 29, 31, 37, 43, 47, 53, 59, 67, 71, 73, 79, 83, 97, 103, 107, 113, 127, 131, 137, 139, 157, 163, 167, 173, 179, 193, 197, 223, 229, 233, 239, 263, 269, 271, 283, 293, 307, 311, 313, 317, 331, 337, 347, 353, 359, 367, 373, 379, 383, 397, 431, 433, 439 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subset of A080608. Numbers 2003, 2017, 2053, 3023, ... are in A080608 but not here.

LINKS

Jeppe Stig Nielsen, Table of n, a(n) for n = 1..10000

EXAMPLE

2003 is not a member since removing a digit will either give 003 which has a leading zero, or give one of the numbers 203 or 200 which are both composite. However, 2003 is in A080608 because all of 2003, 003, 03, 3 are prime.

MATHEMATICA

Rest@ Union@ Nest[Function[{a, p}, Append[a, With[{w = IntegerDigits[p]}, If[# == True, p, 0] &@ AnyTrue[Array[If[First@ # == 0, 1, FromDigits@ #] &@ Delete[w, #] &, Length@ w], ! FreeQ[a, #] &]]]] @@ {#, Prime[Length@ # + 1]} &, Prime@ Range@ PrimePi@ 10, 81] (* Michael De Vlieger, Aug 02 2018 *)

PROG

(PARI) is(n) = !ispseudoprime(n)&&return(0); my(d=digits(n)); #d==1&&return(1); for(i=1, #d, my(v=vecextract(d, Str("^"i))); v[1]!=0&&is(fromdigits(v))&&return(1)); 0

CROSSREFS

Cf. A080608, A080603, A096235-A096246, A322474.

Sequence in context: A234851 A179336 A080608 * A137812 A216578 A094317

Adjacent sequences:  A305349 A305350 A305351 * A305353 A305354 A305355

KEYWORD

nonn,base

AUTHOR

Jeppe Stig Nielsen, Aug 01 2018

STATUS

approved

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Last modified December 16 06:18 EST 2019. Contains 330016 sequences. (Running on oeis4.)