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A146305 Array T(n,m) = 2(2m+3)!(4n+2m+1)!/(m!(m+2)!n!(3n+2m+3)!) read by antidiagonals. 0
1, 1, 2, 3, 5, 5, 13, 20, 21, 14, 68, 100, 105, 84, 42, 399, 570, 595, 504, 330, 132, 2530, 3542, 3675, 3192, 2310, 1287, 429, 16965, 23400, 24150, 21252, 16170, 10296, 5005, 1430, 118668, 161820, 166257, 147420, 115500, 78936, 45045, 19448, 4862, 857956 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

First column is A000260. First, second and third rows are essentially A000108, A002054 and A000917.

LINKS

William G. Brown, Enumeration of Triangulations of the Disk, Proc. Lond. Math. Soc. s3-14 (1964) 746-768.

EXAMPLE

The array starts at row n=0 and column m=0 as

.....1......2.......5......14.......42.......132

.....1......5......21......84......330......1287

.....3.....20.....105.....504.....2310.....10296

....13....100.....595....3192....16170.....78936

....68....570....3675...21252...115500....602316

...399...3542...24150..147420...844074...4628052

..2530..23400..166257.1057224..6301680..35939904

.16965.161820.1186680.7791168.47948670.282285432

MAPLE

T := proc(n, m) 2*(2*m+3)!*(4*n+2*m+1)!/m!/(m+2)!/n!/(3*n+2*m+3)! ; end: for d from 0 to 13 do for m from 0 to d do printf("%d, ", T(d-m, m)) ; od: od:

CROSSREFS

Sequence in context: A079024 A097453 A079125 * A079022 A095296 A157260

Adjacent sequences:  A146302 A146303 A146304 * A146306 A146307 A146308

KEYWORD

easy,nonn,tabl

AUTHOR

R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 29 2008

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Last modified February 14 05:09 EST 2012. Contains 205570 sequences.