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A094535 a(n) is the smallest integer m such that A039995(m)=n.

%I A094535 #24 Aug 08 2022 08:29:30
%S A094535 1,2,13,23,113,131,137,1013,1031,1273,1237,1379,6173,10139,10193,
%T A094535 10379,10397,10937,12397,12379,36137,36173,101397,102371,101937,
%U A094535 102973,103917,106937,109371,109739,123797,123917,123719,346137,193719,346173
%N A094535 a(n) is the smallest integer m such that A039995(m)=n.
%H A094535 Giovanni Resta, <a href="/A094535/b094535.txt">Table of n, a(n) for n = 0..500</a> (first 101 terms from Reinhard Zumkeller)
%H A094535 Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_265.htm">Puzzle 265. Primes embedded</a>, The Prime Puzzles & Problems Connection.
%H A094535 Reinhard Zumkeller, <a href="/A094535/a094535.txt">Illustration of initial terms</a>
%F A094535 A039995(a(n)) = n and A039995(m) != n for m < a(n). - _Reinhard Zumkeller_, Feb 01 2012
%e A094535 a(6) = 137 because 137 is the smallest number m such that A039995(m) = 6; the six numbers 3, 7, 13, 17, 37 & 137 are primes.
%e A094535 See also A205956 for a(100) = 39467139.
%t A094535 cnt[n_] := Count[ PrimeQ@ Union[ FromDigits /@ Subsets[ IntegerDigits[n]]], True]; a[n_] := Block[{k = 1}, While[cnt[k] != n, k++]; k]; Array[a, 21, 0] (* _Giovanni Resta_, Jun 16 2017 *)
%o A094535 (Haskell)
%o A094535 import Data.List (elemIndex)
%o A094535 import Data.Maybe (fromJust)
%o A094535 a094535 n = a094535_list !! n
%o A094535 a094535_list = map ((+ 1) . fromJust . (`elemIndex` a039995_list)) [0..]
%o A094535 -- _Reinhard Zumkeller_, Feb 01 2012
%o A094535 (Python)
%o A094535 from sympy import isprime
%o A094535 from itertools import chain, combinations as combs, count, islice
%o A094535 def powerset(s): # nonempty subsets of s
%o A094535     return chain.from_iterable(combs(s, r) for r in range(1, len(s)+1))
%o A094535 def A039995(n):
%o A094535     ss = set(int("".join(s)) for s in powerset(str(n)))
%o A094535     return sum(1 for k in ss if isprime(k))
%o A094535 def agen():
%o A094535     adict, n = dict(), 0
%o A094535     for k in count(1):
%o A094535         v = A039995(k)
%o A094535         if v not in adict: adict[v] = k
%o A094535         while n in adict: yield adict[n]; n += 1
%o A094535 print(list(islice(agen(), 36))) # _Michael S. Branicky_, Aug 07 2022
%Y A094535 Cf. A039995, A093301, A039997.
%Y A094535 Cf. A205956.
%K A094535 base,nonn
%O A094535 0,2
%A A094535 _Farideh Firoozbakht_, May 08 2004