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 A342533 a(n) is the number of n-gons in A000940 that display symmetry (reflection / rotation). 1
 1, 2, 4, 11, 24, 81, 193, 772, 1920, 8735, 23040 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,2 LINKS Table of n, a(n) for n=3..13. FORMULA a(p) = (2^((p-1)/2)*((p-1)/2)!)/2 for prime p. EXAMPLE Of the A000940(6)=12 hexagons, 11 have symmetry and 1 is asymmetric, so a(6)=11. CROSSREFS Cf. A000940. Sequence in context: A230984 A196195 A205500 * A131434 A100550 A329707 Adjacent sequences: A342530 A342531 A342532 * A342534 A342535 A342536 KEYWORD nonn,more AUTHOR Ian Mooney, Mar 14 2021 STATUS approved

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Last modified March 4 15:18 EST 2024. Contains 370532 sequences. (Running on oeis4.)