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 A025661 #17 Jul 09 2025 12:50:54
%S A025661 0,1,0,2,1,0,3,2,1,0,4,3,2,1,0,5,4,3,2,1,0,6,5,4,3,2,1,0,7,6,5,4,3,2,
%T A025661 1,8,0,7,6,5,4,3,2,9,1,8,0,7,6,5,4,3,10,2,9,1,8,0,7,6,5,4,11,3,10,2,9,
%U A025661 1,8,0,7,6,5,12,4,11,3,10,2,9,1,8,0,7,6,13,5,12,4,11,3,10,2,9,1,8,0,7,14,6,13
%N A025661 Exponent of 6 (value of i) in n-th number of form 6^i*8^j.
%H A025661 Amiram Eldar, <a href="/A025661/b025661.txt">Table of n, a(n) for n = 1..10000</a>
%H A025661 <a href="/index/Se#sequences_which_agree_for_a_long_time">Index entries for sequences which agree for a long time but are different</a>.
%F A025661 a(n) = A122841(A025627(n)). - _Amiram Eldar_, Jul 09 2025
%t A025661 With[{max = 10^12}, IntegerExponent[Sort[Flatten[Table[6^i*8^j, {i, 0, Log[6, max]}, {j, 0, Log[8, max/6^i]}]]], 6]] (* _Amiram Eldar_, Jul 09 2025 *)
%Y A025661 Cf. A025627, A025674, A122841.
%Y A025661 Differs from A025646 at a(1881).
%K A025661 nonn
%O A025661 1,4
%A A025661 _David W. Wilson_