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A092911 Numbers all of whose divisors can be formed using their digits. Divisor digits are a subset of the digits of the number.

%I A092911 #18 May 08 2021 23:00:25
%S A092911 1,11,13,17,19,31,41,61,71,101,103,107,109,113,121,125,127,131,137,
%T A092911 139,149,151,157,163,167,173,179,181,191,193,197,199,211,241,251,271,
%U A092911 281,311,313,317,331,401,419,421,431,461,491,521,541,571
%N A092911 Numbers all of whose divisors can be formed using their digits. Divisor digits are a subset of the digits of the number.
%C A092911 All primes containing 1 are members.
%C A092911 Sequence is a subsequence of A011531. The first nonprime terms of the sequence are 1, 121, 125, 1207, 1255, 1379, 10201, 10379, 11009, 11209, 12419, 12709, 12755, ... - _R. J. Mathar_, Jul 26 2007
%H A092911 Amiram Eldar, <a href="/A092911/b092911.txt">Table of n, a(n) for n = 1..10000</a>
%e A092911 131 is a term. 143 is not a term as the divisor 11 contains two 1's.
%p A092911 isA092911 := proc(n) local digs, digsleft,divs, d,i,j ; digs := convert(n,base,10) ; divs := numtheory[divisors](n) ; for i from 1 to nops(divs) do digsleft := digs ; d := convert(op(i,divs),base,10) ; for j in d do if member(j,digsleft,'jposit') then digsleft := subsop(jposit=NULL,digsleft) ; else RETURN(false) ; fi ; od ; od ; RETURN(true) ; end: for n from 1 to 600 do if isA092911(n) then printf("%d, ",n) ; fi ; od ; # _R. J. Mathar_, Jul 26 2007
%t A092911 subQ[s1_, s2_] := AllTrue[Count[s1, #] & /@ (First /@ (t = Tally[s2])) - Last /@ t, # >= 0 &]; digQ[n1_, n2_] := subQ[IntegerDigits[n1], IntegerDigits[n2]]; seqQ[n_] := AllTrue[Most@Divisors[n], digQ[n, #] &]; Select[Range[600], seqQ] (* _Amiram Eldar_, Nov 12 2020 *)
%o A092911 (Python)
%o A092911 from sympy import divisors
%o A092911 from collections import Counter
%o A092911 def ok(n):
%o A092911   ncounts = Counter(str(n))
%o A092911   for d in divisors(n)[:-1]:
%o A092911     divcounts = Counter(str(d))
%o A092911     if any(ncounts[c] < divcounts[c] for c in divcounts): return False
%o A092911   return True
%o A092911 print(list(filter(ok, range(1, 630)))) # _Michael S. Branicky_, May 08 2021
%Y A092911 Cf. A011531, A062634, A092912.
%K A092911 base,nonn
%O A092911 1,2
%A A092911 _Amarnath Murthy_, Mar 14 2004
%E A092911 Corrected and extended by _R. J. Mathar_, Jul 26 2007