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A333076 Irregular table read by rows: Take an octagon with all diagonals drawn, as in A333075. Then T(n,k) = number of k-sided polygons in that figure for k >= 3. 4
56, 24, 800, 608, 64, 16, 4136, 3400, 1272, 464, 40, 13840, 10800, 5296, 1264, 288, 64, 33160, 30048, 14744, 4456, 840, 152, 32, 70832, 62208, 30848, 8656, 1936, 288, 48, 129624, 124224, 61560, 19312, 4168, 840, 64, 16, 0, 8, 225200, 210608, 107552, 32768 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See the links in A333075 for images of the octagons.

LINKS

Lars Blomberg, Table of n, a(n) for n = 1..207

EXAMPLE

An octagon with no other points along its edges, n = 1, contains 56 triangles, 24 quadrilaterals and no other n-gons, so the first row is [56,24]. An octagon with 1 point dividing its edges, n = 2, contains 800 triangles, 608 quadrilaterals, 64 pentagons, 16 hexagons and no other n-gons, so the second row is [800,608,64,16].

Table begins:

56,24;

800,608,64,16;

4136,3400,1272,464,40;

13840,10800,5296,1264,288,64;

33160,30048,14744,4456,840,152,32;

70832,62208,30848,8656,1936,288,48;

The rows sums are A333075.

CROSSREFS

Cf. A333075 (regions), A333109 (verices), A333110 (edges), A331931, A331906, A007678, A092867, A331452.

Sequence in context: A005932 A109737 A092077 * A033376 A300449 A224343

Adjacent sequences:  A333073 A333074 A333075 * A333077 A333078 A333079

KEYWORD

nonn,tabf

AUTHOR

Scott R. Shannon and N. J. A. Sloane, Mar 07 2020

EXTENSIONS

a(32) and beyond from Lars Blomberg, May 14 2020

STATUS

approved

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Last modified May 31 09:30 EDT 2020. Contains 334748 sequences. (Running on oeis4.)