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 A191992 #18 Dec 05 2016 16:21:42
%S A191992 14,26,38,49,510,612,714,815,916,1018,1120,1221,1322,1424,1525,1626,
%T A191992 1727,1828,1930,2032,2133,2234,2335,2436,2538,2639,2740,2842,2944,
%U A191992 3045,3146,3248,3349,3450,3551,3652,3754,3855,3956,4057,4158,4260,4362,4463,4564,4665,4766,4868,4969,5070,5172,5274,5375,5476
%N A191992 Concatenation of n and the n-th composite number.
%H A191992 Jens Kruse Andersen, <a href="/A191992/b191992.txt">Table of n, a(n) for n = 1..10000</a>
%t A191992 Module[{upto=55,cmps,len},cmps=Select[Range[10*upto],CompositeQ];len= Min[ Length[ cmps],upto];#[[1]]*10^IntegerLength[#[[2]]]+#[[2]]&/@ Thread[{ Range[ len],Take[cmps,len]}]] (* _Harvey P. Dale_, Dec 05 2016 *)
%o A191992 (PARI) n=0;for(k=4,1e3,if(isprime(k),k++);print1(n++k", ")) \\ _Charles R Greathouse IV_, Jun 21 2011
%Y A191992 Cf. A045532, the prime analog of this sequence.
%Y A191992 Cf. A246801, primes in this sequence.
%K A191992 nonn,base
%O A191992 1,1
%A A191992 _Kausthub Gudipati_, Jun 20 2011