This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A385477 #22 Jul 08 2025 03:05:33
%S A385477 33,35,55,57,75,77,333,335,355,357,375,377,533,535,537,553,555,573,
%T A385477 575,735,737,753,755,775,777,3333,3335,3337,3353,3355,3357,3375,3377,
%U A385477 3535,3537,3553,3555,3573,3575,3577,3735,3737,3753,3755,3757,3773,3775,3777,5335,5337,5353,5355,5357
%N A385477 Composite numbers whose digits are odd prime numbers.
%H A385477 Mia Boudreau, <a href="/A385477/b385477.txt">Table of n, a(n) for n = 1..5000</a>
%p A385477 A:=3,5,7: B:= [A]:
%p A385477 for d from 2 to 4 do B:= map(f,B); A:= A,op(B) od:
%p A385477 remove(isprime,[A]); # _Robert Israel_, Jun 30 2025
%t A385477 Select[Range[1, 6000, 2], CompositeQ[#] && AllTrue[IntegerDigits[#], MemberQ[{3, 5, 7}, #1] &] &] (* _Amiram Eldar_, Jun 30 2025 *)
%o A385477 (Python)
%o A385477 from sympy import isprime
%o A385477 from itertools import count, islice, product
%o A385477 def agen(): yield from (t for d in count(2) for p in product("357", repeat=d) if not isprime(t:=int("".join(p))))
%o A385477 print(list(islice(agen(), 53))) # _Michael S. Branicky_, Jun 30 2025
%Y A385477 Subsequence of A061371.
%Y A385477 Subsequence of A320062.
%Y A385477 Cf. A061372, A087363.
%K A385477 nonn,base
%O A385477 1,1
%A A385477 _Enrique Navarrete_, Jun 30 2025