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A051785
Number of letters in n-th Catalan number.
0
2, 3, 4, 6, 4, 3, 3, 4, 3, 3, 4, 5, 6, 7, 6, 5, 6, 6, 5, 4, 7, 8, 9, 11, 9, 8, 8, 9, 8, 6, 8, 9, 10, 12, 10, 9, 9, 10, 9, 8, 10, 11, 12, 14, 12, 11, 11, 12, 11, 9, 11, 12, 13, 15, 13, 12, 12, 13, 12, 8, 10, 11, 12, 14, 12, 11, 11, 12, 11, 7, 9, 10, 11, 13, 11, 10, 10, 11, 10, 8, 10, 11
OFFSET
1,1
REFERENCES
J. Gili, Catalan Grammar, Dolphin. Oxford 1993, p. 39.
R. P. Stanley, Enumerative Combinatorics, vol. 2, problem 6.24.
LINKS
Amer. Math. Monthly 103 (1996), see pages 538 and 577.
Catalan Institute of America, Home Page
EXAMPLE
In Catalan: un, dos, tres, quatre, cinc, sis, set, vuit, nou, deu, onze, dotze, tretze, catorze, quinze, setze, disset, divuit, dinou, vint, ...
CROSSREFS
Sequence in context: A321479 A128332 A074103 * A144825 A159633 A049044
KEYWORD
nonn,easy,word,nice
AUTHOR
N. J. A. Sloane and Richard Borcherds, Dec 09 1999
EXTENSIONS
More terms from F. Xavier Noria (fxn(AT)retemail.es) and Manuel Valdivia Prades (mvaldivia(AT)ugr.es), Dec 10 1999
STATUS
approved