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 A134554 #9 Sep 18 2015 03:40:28
%S A134554 0,111,111,222,333,555,888,131313,212121,343434,555555,898989,
%T A134554 144144144,233233233,377377377,610610610,987987987,159715971597,
%U A134554 258425842584,418141814181,676567656765,109461094610946,177111771117711
%N A134554 Concatenate the terms of three copies of the Fibonacci sequence.
%C A134554 Leading zeros are omitted.
%F A134554 a(n)=A074842(A000045(n+1)). - _R. J. Mathar_, Jan 29 2008
%p A134554 catL := proc(i,j) i*10^(max(1,ilog10(j)+1))+j ; end: Fib := proc(n) if n = 0 then 0 ; else combinat[fibonacci](n+1) ; fi ; end: A134554 := proc(n) local f ; f := Fib(n) ; catL( catL(f,f),f) ; end: seq(A134554(n),n=0..25) ; # _R. J. Mathar_, Jan 29 2008
%p A134554 with(combinat): concat:=proc(a,b) local bb: bb:=nops(convert(b,base,10)): 10^bb*a+b end proc: seq(concat(fibonacci(p),concat(fibonacci(p),fibonacci(p))),p=1..20); # _Emeric Deutsch_, Jan 29 2008
%t A134554 concatfib[n_]:=Module[{idn=IntegerDigits[n]},FromDigits[Join[idn,idn,idn]]]; concatfib/@Fibonacci[Range[0,30]] (* _Harvey P. Dale_, Jul 13 2015 *)
%Y A134554 Cf. A000045, A074842.
%K A134554 nonn,base,easy
%O A134554 0,2
%A A134554 Deuard Worthen (deuard(AT)tx.rr.com), Jan 23 2008, at the suggestion of _N. J. A. Sloane_
%E A134554 More terms from _R. J. Mathar_ and _Emeric Deutsch_, Jan 29 2008