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A130380 Catalan numbers halved and rounded to the next integer. 3
1, 1, 1, 3, 7, 21, 66, 215, 715, 2431, 8398, 29393, 104006, 371450, 1337220, 4847423, 17678835, 64822395, 238819350, 883631595, 3282060210, 12233133510, 45741281820, 171529806825, 644952073662, 2430973200726, 9183676536076 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A130918.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

FORMULA

a(n) = ceiling(A000108(n)/2) = (A000108(n)+A036987(n))/2.

MATHEMATICA

Ceiling[CatalanNumber[Range[0, 30]]/2] (* Harvey P. Dale, Feb 16 2014 *)

PROG

(MIT Scheme:) (define (A130380 n) (floor->exact (/ (+ (A000108 n) 1) 2)))

CROSSREFS

Sequence in context: A148675 A148676 A105864 * A097147 A148677 A240506

Adjacent sequences:  A130377 A130378 A130379 * A130381 A130382 A130383

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jun 11 2007

STATUS

approved

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Last modified May 26 17:16 EDT 2022. Contains 354092 sequences. (Running on oeis4.)