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 A054542 A Catalan-like sequence. 1
 1, 2, 4, 12, 36, 116, 382, 1287, 4420, 15397, 54264, 193154, 693374, 2507288, 9124560, 33393355, 122821380, 453756765, 1683107800, 6265751310, 23402516280, 87670790155, 329337229104, 1240292449350, 4681874312510 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This sequence (k=2, p=2) belongs to a family of Catalan-like sequences that merit further investigation. The ceiling is taken in order to eliminate the fractional parts. Are there combinations of k and p for which the ceiling is unnecessary? REFERENCES Felix Goldberg, A problem relating to a family of Catalan-like sequences, forthcoming. LINKS FORMULA a(n) = Ceiling ( 1/(n+k)*C(pn, n) ), where k=2, p=2 (in the standard Catalan sequence k=1 and p=2). EXAMPLE a(6)=116 because 1/(6+2)*C(12,6) is 115.5 and taking the ceiling we obtain 116. CROSSREFS Cf. A000108. Sequence in context: A149842 A149843 A217699 * A214198 A117757 A009623 Adjacent sequences:  A054539 A054540 A054541 * A054543 A054544 A054545 KEYWORD nonn AUTHOR Felix Goldberg (sgefelix(AT)t2.technion.ac.il), Apr 10 2000 EXTENSIONS More terms from James A. Sellers, Apr 11 2000 STATUS approved

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