cp's OEIS Frontend

A127355 Primes with prime digit counts. The digit count numerically summarizes the frequency of digits 0 through 9 in that order when they occur in a number.

%I A127355 #11 Oct 10 2019 11:48:17
%S A127355 3,7,17,23,71,101,103,107,109,113,127,131,137,173,199,223,233,271,311,
%T A127355 313,317,331,359,367,409,479,499,593,673,677,701,709,773,797,907,919,
%U A127355 929,947,953,977,991,1009,1123,1129,1193,1213,1217,1223,1231,1277,1291
%N A127355 Primes with prime digit counts. The digit count numerically summarizes the frequency of digits 0 through 9 in that order when they occur in a number.
%C A127355 Compare with "Look And Say" version A056815.
%H A127355 Reinhard Zumkeller, <a href="/A127355/b127355.txt">Table of n, a(n) for n = 1..10000</a>
%F A127355 A010051(a(n)) * A010051(A047842(a(n))) = 1. - _Reinhard Zumkeller_, Apr 14 2014
%e A127355 The primes 479,991,1747 respectively have digit counts 141719 (one 4,one 7,one 9), 1129 (one 1, two 9's), 111427 (one 1, one 4, two 7's) which are also prime; So they belong to the sequence.
%t A127355 dc[n_] :=FromDigits@Flatten@Select[Table[{DigitCount[n, 10, k], k}, {k, 0, 9}], #[[1]] > 0 &];Select[Prime@Range[210], PrimeQ[dc[ # ]] &] (* _Ray Chandler_, Jan 16 2007 *)
%o A127355 (Haskell)
%o A127355 a127355 n = a127355_list !! (n-1)
%o A127355 a127355_list = filter ((== 1) . a010051' . a047842) a000040_list
%o A127355 -- _Reinhard Zumkeller_, Apr 14 2014
%Y A127355 Cf. A047842, A127354.
%K A127355 nonn,base
%O A127355 1,1
%A A127355 _Lekraj Beedassy_, Jan 11 2007
%E A127355 Corrected by _Ray Chandler_, Jan 16 2007