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A179025 Primes with a 2 as the only prime digit. 2
2, 29, 211, 241, 269, 281, 421, 821, 829, 929, 1021, 1129, 1201, 1249, 1289, 1291, 1429, 1621, 2011, 2069, 2081, 2089, 2099, 2111, 2141, 2161, 2411, 2441, 2609, 2689, 2699, 2801, 2819, 2861, 2909, 2969, 2999, 4021, 4129, 4201, 4211, 4219, 4241, 4261 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This is a proper subsequence of A179024. - Jianing Song, Jul 10 2018

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

Digs:= [0, 1, 2, 4, 6, 8, 9]:

f:= proc(n) local L, x;

  L:= convert(n, base, 7);

  if numboccur(2, L) <> 1 then return NULL fi;

  x:= add(Digs[L[i]+1]*10^(i-1), i=1..nops(L));

  if isprime(x) then x fi

end proc:

map(f, [$1..2000]); # Robert Israel, Jul 10 2018

CROSSREFS

Cf. A179024.

Sequence in context: A132412 A009772 A179024 * A244599 A261268 A020460

Adjacent sequences:  A179022 A179023 A179024 * A179026 A179027 A179028

KEYWORD

nonn,base

AUTHOR

Lekraj Beedassy, Jun 25 2010

EXTENSIONS

Terms confirmed by Ray Chandler, Jul 13 2010

STATUS

approved

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Last modified August 20 05:00 EDT 2019. Contains 326139 sequences. (Running on oeis4.)