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A046653 Triangle of rooted planar maps. 2
1, 1, 1, 1, 1, 2, 1, 2, 3, 4, 1, 2, 8, 12, 14, 1, 3, 12, 30, 43, 49, 1, 3, 22, 63, 134, 189, 216, 1, 4, 31, 133, 323, 608, 888, 984, 1, 4, 48, 238, 759, 1671, 2988, 4332, 4862, 1, 5, 64, 422, 1594, 4260, 8772, 15126, 22011, 24739, 1, 5, 90, 694, 3210, 10002, 23986, 46923, 79214, 115131, 130338, 1, 6, 115, 1106, 6024, 22176, 60813, 135097, 255277, 424034, 616395, 701584 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

2,6

LINKS

Table of n, a(n) for n=2..79.

W. G. Brown, Enumeration of non-separable planar maps, Canad. J. Math., 15 (1963), 526-545.

W. G. Brown, Enumeration of non-separable planar maps [Annotated scanned copy]

FORMULA

Reference gives generating functions.

EXAMPLE

Triangle begins:

1;

1, 1;

1, 1, 2;

1, 2, 3, 4;

1, 2, 8, 12, 14;

1, 3, 12, 30, 43, 49;

...

MAPLE

# uses function L(., .) from A046650

for n from 2 to 13 do

for m from n to 2 by -1 do

    printf("%d, ", L(n, m)) ;

end do:

printf("\n") ;

end do: # R. J. Mathar, Apr 13 2019

CROSSREFS

Cf. A046650 (diagonal), A000087 (row sums).

Sequence in context: A309776 A255560 A328472 * A308897 A162190 A134292

Adjacent sequences:  A046650 A046651 A046652 * A046654 A046655 A046656

KEYWORD

tabl,nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from R. J. Mathar, Apr 13 2019

STATUS

approved

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Last modified October 23 08:57 EDT 2019. Contains 328345 sequences. (Running on oeis4.)