Original entry on oeis.org
1, 2, 5, 16, 48, 164, 599, 1952
Offset: 0
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
A262586
Square array T(n,m) (n>=0, m>=0) read by antidiagonals downwards giving number of rooted triangulations of type [n,m] up to orientation-preserving isomorphisms.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 4, 5, 6, 5, 6, 16, 21, 26, 24, 19, 48, 88, 119, 147, 133, 49, 164, 330, 538, 735, 892, 846, 150, 559, 1302, 2310, 3568, 4830, 5876, 5661, 442, 1952, 5005, 9882, 16500, 24596, 33253, 40490, 39556, 1424, 6872, 19504, 41715, 75387, 120582, 176354, 237336, 290020, 286000, 4522
Offset: 0
Array begins:
==============================================================
n\k | 0 1 2 3 4 5 6 ...
----+---------------------------------------------------------
0 | 1 1 1 4 6 19 49 ...
1 | 1 2 5 16 48 164 559 ...
2 | 1 6 21 88 330 1302 5005 ...
3 | 5 26 119 538 2310 9882 41715 ...
4 | 24 147 735 3568 16500 75387 338685 ...
5 | 133 892 4830 24596 120582 578622 2730728 ...
6 | 846 5876 33253 176354 900240 4493168 22037055 ...
7 | 5661 40490 237336 1298732 6849810 35286534 178606610 ...
...
The first few antidiagonals are:
1,
1,1,
1,2,1,
4,5,6,5,
6,16,21,26,24,
19,48,88,119,147,133,
49,164,330,538,735,892,846,
...
- Andrew Howroyd, Table of n, a(n) for n = 0..1325 (first 51 antidiagonals).
- Jean-François Alcover, Mathematica code
- W. G. Brown, Enumeration of Triangulations of the Disk, Proc. Lond. Math. Soc. s3-14 (1964) 746-768. [Annotated scanned copy]. See Table 1 (with a typo at G(n=1,m=6)).
- L. March and C. F. Earl, On Counting Architectural Plans, Environment and Planning B, 4 (1977), 57-80. See Table 2.
-
A262586 := proc(n,m)
BrownG(n,m) ; # procedure in A210696
end proc:
for d from 0 to 12 do
for n from 0 to d do
printf("%d,",A262586(n,d-n)) ;
end do:
end do: # R. J. Mathar, Oct 21 2015
-
(* See LINKS section. *)
-
\\ See Links in A169808 for PARI program file.
{ for(n=0, 7, for(k=0, 7, print1(OrientedTriangs(n,k), ", ")); print) } \\ Andrew Howroyd, Nov 23 2024
A002711
Triangulations of the disk G_{n,2}.
Original entry on oeis.org
1, 5, 21, 119, 735, 4830, 33253, 237336, 1743588, 13114465, 100591491, 784428522, 6204258970, 49675571820, 402013608525, 3284214703056, 27055525967324, 224557688302164, 1876374953765620, 15774315150669075, 133345566025874055, 1132905339504465590, 9669675838370401035
Offset: 0
- N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
A005498
Triangulations of the disk G_{2,n}.
Original entry on oeis.org
1, 6, 21, 88, 330, 1302, 5005, 19504, 75582, 294140, 1144066, 4458192, 17383860, 67866918, 265182525, 1037169760, 4059928950, 15905412468, 62359143990, 244662838160, 960566918220, 3773656396796, 14833897694226, 58343359313568, 229591913401900, 903936171565752, 3560597348629860
Offset: 0
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
A005495
Number of triangulations of the disk G_{n,3}.
Original entry on oeis.org
4, 16, 88, 538, 3568, 24596, 176354, 1298732, 9788838, 75190990, 586994548, 4646450800, 37225608048, 301400446752, 2463161448024, 20297411421166, 168503717726980, 1408243135178256, 11840473621942108, 100102553809842544
Offset: 0
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
A005499
Triangulations of the disk G_{3,n}.
Original entry on oeis.org
5, 26, 119, 538, 2310, 9882, 41715, 175088, 730626, 3037510, 12584726, 52003792, 214401024, 882233898, 3624161175, 14865947668, 60898934250, 249184153548, 1018532686314, 4159265561360, 16970015555220, 69183689403686, 281844056190294, 1147419353238816, 4668368905854840, 18982659409726792
Offset: 0
- N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
Showing 1-6 of 6 results.