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 A108761 #12 Sep 25 2020 06:00:17
%S A108761 1,10,13,100,130,169,1000,1300,1690,2197,10000,13000,16900,21970,
%T A108761 28561,100000,130000,169000,219700,285610,371293,1000000,1300000,
%U A108761 1690000,2197000,2856100,3712930,4826809,10000000,13000000,16900000
%N A108761 Numbers of the form (10^i)*(13^j), with i, j >= 0.
%H A108761 Reinhard Zumkeller, <a href="/A108761/b108761.txt">Table of n, a(n) for n = 1..10000</a>
%F A108761 Sum_{n>=1} 1/a(n) = (10*13)/((10-1)*(13-1)) = 65/54. - _Amiram Eldar_, Sep 25 2020
%F A108761 a(n) ~ exp(sqrt(2*log(10)*log(13)*n)) / sqrt(130). - _Vaclav Kotesovec_, Sep 25 2020
%t A108761 n = 10^7; Flatten[Table[10^i*13^j, {i, 0, Log10[n]}, {j, 0, Log[13, n/10^i]}]] // Sort (* _Amiram Eldar_, Sep 25 2020 *)
%o A108761 (Haskell)
%o A108761 import Data.Set (singleton, deleteFindMin, insert)
%o A108761 a108761 n = a108761_list !! (n-1)
%o A108761 a108761_list = f $ singleton (1,0,0) where
%o A108761 f s = y : f (insert (10 * y, i + 1, j) $ insert (13 * y, i, j + 1) s')
%o A108761 where ((y, i, j), s') = deleteFindMin s
%o A108761 -- _Reinhard Zumkeller_, May 15 2015
%Y A108761 Cf. A107326, A107364, A107462, A107466, A107710, A108056, A107764, A108748, A108090.
%K A108761 nonn,easy
%O A108761 1,2
%A A108761 Douglas Winston (douglas.winston(AT)srupc.com), Jun 24 2005