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A046892 Number of permutations of digits of A046891(n) that are primes.

%I A046892 #15 Feb 18 2024 05:44:15
%S A046892 0,1,2,3,4,5,8,9,10,11,13,16,18,22,31,34,37,39,40,49,52,64,80,87,93,
%T A046892 115,121,144,149,160,172,225,233,298,299,308,384,399,408,423,475,484,
%U A046892 569,571,738,806,835,863,934,1247,1413,1525,1739,1775,2282,2303,2325
%N A046892 Number of permutations of digits of A046891(n) that are primes.
%H A046892 Michael S. Branicky, <a href="/A046892/b046892.txt">Table of n, a(n) for n = 1..91</a>
%t A046892 a = {}; b = -1; Do[c = Count[ PrimeQ[ FromDigits /@ Permutations[IntegerDigits[n]]], True]; If[c > b, b = c; a = Append[a, c]], {n, 1, 10^8}]; a
%o A046892 (Python)
%o A046892 from sympy import prime
%o A046892 from gmpy2 import is_prime
%o A046892 from sympy.utilities.iterables import multiset_permutations as mp
%o A046892 from itertools import count, islice, combinations_with_replacement as mc
%o A046892 def f(n): return sum(1 for p in mp(str(n)) if is_prime(t:=int("".join(p))))
%o A046892 def bgen(d):
%o A046892     for f in "123456789":
%o A046892         yield from map(int, (f+"".join(m) for m in mc("0123456789", d-1)))
%o A046892 def agen():
%o A046892     record = -1
%o A046892     for d in count(1):
%o A046892         for k in bgen(d):
%o A046892             v = f(k)
%o A046892             if v > record:
%o A046892                 record = v
%o A046892                 yield v
%o A046892 print(list(islice(agen(), 30))) # _Michael S. Branicky_, Feb 17 2024
%Y A046892 Cf. A039999, A046891.
%K A046892 nonn,base
%O A046892 1,3
%A A046892 _David W. Wilson_