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 A130380 #10 Feb 02 2018 16:38:50 %S A130380 1,1,1,3,7,21,66,215,715,2431,8398,29393,104006,371450,1337220, %T A130380 4847423,17678835,64822395,238819350,883631595,3282060210,12233133510, %U A130380 45741281820,171529806825,644952073662,2430973200726,9183676536076 %N A130380 Catalan numbers halved and rounded to the next integer. %C A130380 Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A130918. %H A130380 Vincenzo Librandi, <a href="/A130380/b130380.txt">Table of n, a(n) for n = 0..1000</a> %F A130380 a(n) = ceiling(A000108(n)/2) = (A000108(n)+A036987(n))/2. %t A130380 Ceiling[CatalanNumber[Range[0,30]]/2] (* _Harvey P. Dale_, Feb 16 2014 *) %o A130380 (MIT Scheme:) (define (A130380 n) (floor->exact (/ (+ (A000108 n) 1) 2))) %K A130380 nonn %O A130380 0,4 %A A130380 _Antti Karttunen_, Jun 11 2007