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 A179025 Primes with a single 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 MATHEMATICA Select[Prime[Range[600]], DigitCount[#, 10, 2]==1&&NoneTrue[ DeleteCases[ IntegerDigits[#], 2], PrimeQ]&] (* Harvey P. Dale, Feb 20 2022 *) CROSSREFS Cf. A179024. Sequence in context: A342454 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 Definition clarified by Harvey P. Dale, Feb 20 2022 STATUS approved

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Last modified September 28 20:28 EDT 2023. Contains 365737 sequences. (Running on oeis4.)