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 A095221 #12 Nov 22 2022 02:56:00 %S A095221 0,0,0,2,0,0,5,6,0,0,4,0,4,4,0,12,15,0,16,0,3,4,6,12,0,16,0,8,3,0,18, %T A095221 28,15,16,25,0,14,10,33,20,27,24,27,4,0,36,35,12,29,0,48,4,14,0,15,4, %U A095221 18,28,3,0,28,60,45,60,55,48,13,52,0,50,14,36,12,72,0,20,4,72,74,60,54,24,65 %N A095221 (Concatenation 1,2,3,...,n) mod n. %H A095221 Michael S. Branicky, <a href="/A095221/b095221.txt">Table of n, a(n) for n = 1..10000</a> %F A095221 a(n) = A007908(n) mod n. - _Michel Marcus_, Nov 21 2022 %e A095221 a(4) = 1234 mod 4 = 2. %o A095221 (Python) %o A095221 from itertools import count, islice %o A095221 def agen(): %o A095221 s = "0" %o A095221 for n in count(1): s += str(n); yield int(s)%n %o A095221 print(list(islice(agen(), 83))) # _Michael S. Branicky_, Nov 21 2022 %Y A095221 Cf. A007908, A094151. %K A095221 base,nonn,easy %O A095221 1,4 %A A095221 _Amarnath Murthy_, Jun 10 2004 %E A095221 More terms from _John W. Layman_, Jul 29 2005