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 A097252 #18 Apr 04 2025 15:02:32
%S A097252 0,5,30,35,180,185,210,215,1080,1085,1110,1115,1260,1265,1290,1295,
%T A097252 6480,6485,6510,6515,6660,6665,6690,6695,7560,7565,7590,7595,7740,
%U A097252 7745,7770,7775,38880,38885,38910,38915,39060,39065,39090,39095,39960,39965
%N A097252 Numbers whose set of base 6 digits is {0,5}.
%C A097252 n such that there exists a permutation p_1, ..., p_n of 1, ..., n such that i + p_i is a power of 6 for every i.
%H A097252 Vincenzo Librandi, <a href="/A097252/b097252.txt">Table of n, a(n) for n = 0..500</a>
%F A097252 a(n) = 5*A033043(n).
%F A097252 a(2n) = 6*a(n), a(2n+1) = a(2n)+5.
%t A097252 fQ[n_]:=Union@Join[{0,5},IntegerDigits[n,6]]=={0,5};Select[Range[0,40000],fQ] (* _Vincenzo Librandi_, May 25 2012 *)
%t A097252 FromDigits[#,6]&/@Tuples[{ 0,5},6] (* _Harvey P. Dale_, Aug 15 2021 *)
%o A097252 (Magma) [n: n in [0..40000] | Set(IntegerToSequence(n, 6)) subset {0, 5}]; // _Vincenzo Librandi_, May 25 2012
%o A097252 (Python)
%o A097252 def A079252(n): return 5*int(bin(n)[2:],6) # _Chai Wah Wu_, Apr 04 2025
%Y A097252 Cf. A001196, A005823, A007088, A033043, A097251-A097262.
%K A097252 nonn,base
%O A097252 0,2
%A A097252 _Ray Chandler_, Aug 03 2004