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A210664 Square array read by upwards antidiagonals: T(m,n) (m>=0, n>=1) = number of simple triangulations of a closed region in the plane with m+3 given external edges and 3n+m internal edges. 2
1, 1, 0, 1, 2, 1, 1, 5, 6, 3, 1, 9, 20, 22, 12, 1, 14, 50, 85, 91, 52 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

REFERENCES

P. N. Rathie, A census of simple planar triangulations, J. Combin. Theory, B 16 (1974), 134-138.

LINKS

Table of n, a(n) for n=0..20.

EXAMPLE

Array begins:

1 0 1 3 12 52 ... (A000256)

1 2 6 22 91 ...

1 5 20 85 385 ...

1 9 50 254 1287 ...

1 14 105 644 3696 ...

1 20 196 1448 9468 ...

...

CROSSREFS

First row is A000256.

Columns are A000012, A000096, A002415, A004305.

Sequence in context: A293219 A266572 A266681 * A176093 A092437 A064814

Adjacent sequences:  A210661 A210662 A210663 * A210665 A210666 A210667

KEYWORD

nonn,tabl

AUTHOR

N. J. A. Sloane, Mar 28 2012

STATUS

approved

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Last modified April 8 05:55 EDT 2020. Contains 333312 sequences. (Running on oeis4.)