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 A179033 Emirps with a single 2 as the only prime digit. 2
 1021, 1201, 1249, 1429, 9029, 9209, 9241, 9421, 10429, 11621, 12109, 12119, 12149, 12491, 12611, 12619, 12641, 12689, 12809, 12841, 12919, 14029, 14621, 14629, 14821, 14929, 16249, 16829, 18269, 19219, 19249, 19421, 90121, 90821, 91121 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE Note that 2 and 929 are not emirps because they are palindromes. MAPLE Dmax:= 6: # to get all terms with up to Dmax digits Res:= NULL: npd:= [0, 1, 4, 6, 8, 9]: for dd from 3 to Dmax do R:= [seq(seq([seq(npd[j+1], j=convert(6*x+j, base, 6))], x=[\$6^(dd-3) .. 2*6^(dd-3)-1, \$5*6^(dd-3)..6^(dd-2)-1]), j=[1, 5])]; for p from 2 to dd-1 do for r in R do x:= [op(r[1..p-1]), 2, op(r[p..-1])]; v1:= add(x[i]*10^(i-1), i=1..dd); v2:= add(x[-i]*10^(i-1), i=1..dd); if v1 < v2 and isprime(v1) and isprime(v2) then Res:= Res, v1, v2; if min(v1, v2) < 10^3 then print(dd, p, r, x, v1, v2) fi fi od od od: sort([Res]); # Robert Israel, Jun 02 2016 MATHEMATICA emrp[n_]:=Module[{idn=IntegerDigits[n], rev}, rev=Reverse[idn]; PrimeQ[FromDigits[rev]]&&rev!=idn] only2[n_]:=DigitCount[n, 10, {3, 5, 7}]=={0, 0, 0}&&DigitCount[n, 10, 2]==1 Select[Select[Prime[Range[10000]], emrp], only2] (* Harvey P. Dale, Jan 22 2011 *) CROSSREFS Cf. A006567, A179032. Sequence in context: A088290 A209620 A179032 * A082059 A081633 A020388 Adjacent sequences: A179030 A179031 A179032 * A179034 A179035 A179036 KEYWORD base,less,nonn AUTHOR Lekraj Beedassy, Jun 25 2010 EXTENSIONS Terms confirmed by Ray Chandler, Jul 13 2010 Definition improved by Harvey P. Dale, Jul 17 2010 STATUS approved

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Last modified January 28 19:04 EST 2023. Contains 359905 sequences. (Running on oeis4.)