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 A273397 #21 Jan 21 2017 19:01:45 %S A273397 1,1,1,5,377,267914296,1725375039079340637797070384, %T A273397 202401005213503038261932567177107618332887918916819829782797456368284639448671475316218754 %N A273397 a(n) = Fibonacci(Catalan(n)). %C A273397 Next term, a(8), which has 299 digits, is too large to include. Counterpart to A273398. %C A273397 The number of digits of a(n) grows faster than Fibonacci(n), in contrast to A273398, and faster than Catalan(n-2), but slower than Catalan(n-1) or Catalan(n). %H A273397 Alois P. Heinz, <a href="/A273397/b273397.txt">Table of n, a(n) for n = 0..8</a> %F A273397 a(n) = A000045(A000108(n)). %e A273397 For n = 3, a(3) = Fibonacci(Catalan(3)) = Fibonacci(5) = 5. %p A273397 a:= n-> (<<0|1>, <1|1>>^(binomial(2*n, n)/(n+1)))[1, 2]: %p A273397 seq(a(n), n=0..8); # _Alois P. Heinz_, Jan 20 2017 %t A273397 Fibonacci[CatalanNumber[Range[0, 7]]] %o A273397 (PARI) for(n=0,7, cn=binomial(2*n, n)/(n+1); print1(fibonacci(cn) ",")) %Y A273397 Cf. A000045 (Fibonacci), A000108(Catalan), A263986, A273398 (related sequences with Fibonacci and Catalan numbers), A281450. %K A273397 nonn,easy %O A273397 0,4 %A A273397 _Waldemar Puszkarz_, May 21 2016