document.write( "Question 1099746: What is the next number in the series 1,1,2,5,14,42?
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Algebra.Com's Answer #714213 by richwmiller(17219)\"\" \"About 
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The Catalan numbers (1, 2, 5, 14, 42, 132, 429, 1430, 4862, 16796, 58786, 208012, 742900, 2674440, 9694845, ...), named after Eugène Charles Catalan (1814–1894), arise in a number of problems in combinatorics. \r
\n" ); document.write( "\n" ); document.write( "Among other things, the Catalan numbers describe:\r
\n" ); document.write( "\n" ); document.write( "the number of ways a polygon with n+2 sides can be cut into n triangles
\n" ); document.write( "the number of ways to use n rectangles to tile a stairstep shape (1, 2, ..., n−1, n).
\n" ); document.write( "the number of ways in which parentheses can be placed in a sequence of numbers to be multiplied, two at a time
\n" ); document.write( "the number of planar binary trees with n+1 leaves
\n" ); document.write( "the number of paths of length 2n through an n-by-n grid that do not rise above the main diagonal \n" ); document.write( "
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