A307456 - OEIS

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A307456

a(n) is the number of canonical polygons with 2n edges having exactly 2 lines of reflection symmetry.

8

2, 2, 1, 4, 11, 24, 47, 99, 211, 437, 909, 1925

(list; graph; refs; listen; history; text; internal format)

OFFSET

2,1

LINKS

Table of n, a(n) for n=2..13.

Lars Blomberg, Examples of canonical polygons with exactly 2 lines of reflection symmetry

CROSSREFS

Cf. A052436, A307387, A307391, A307426, A307454, A307455, A307456, A307519.

Sequence in context: A185041 A086873 A101560 * A291260 A350825 A218529

Adjacent sequences: A307453 A307454 A307455 * A307457 A307458 A307459

KEYWORD

nonn,more

AUTHOR

Lars Blomberg, Apr 09 2019

STATUS

approved