A350191 -id:A350191 - cp's OEIS frontend

A289893 Number of maximum independent vertex sets in the n-triangular honeycomb queen graph.

1, 3, 3, 2, 23, 18, 6, 270, 166, 28, 4842, 2532, 244, 120052, 49620, 2544, 3852972, 1270832, 35600, 156145080, 40668960, 659632, 7746956424, 1606984224, 15106128, 460265296128, 75930070688, 425802176

Offset: 1

Eric W. Weisstein, Jul 14 2017

Eric Weisstein's World of Mathematics, Maximum Independent Vertex Set

Cf. A002047, A350041, A350191, A004396 (independence number).

a(3*n+1) agrees with A002047(n) for available terms.

a(18)-a(19) from Vaclav Kotesovec, Dec 13 2021
a(20) from Vaclav Kotesovec, Dec 16 2021
a(21)-a(28) from Martin Ehrenstein, Dec 17 2021

A350041 Number of ways of placing maximum number of nonattacking rooks on a triangular board with edge-length n (symmetric solutions count only once).

Original entry on oeis.org

1, 1, 1, 1, 5, 3, 1, 45, 29, 6, 807, 422, 46, 20022, 8270, 424, 642162, 211848

Offset: 1

Alain Brobecker, Dec 10 2021

The rooks placements are considered different when they cannot be obtained by a rotation and/or reflection of another solution that leaves the board inchanged. - Alain Brobecker, Dec 19 2021

a(n) = A350191(n) for n <> 10,13,16,19,... - Vaclav Kotesovec, Dec 20 2021

Alain Brobecker, Non Attacking Rooks on Hexhex and Triangular boards

Cf. A004396, A289893, A350191.

a(17)-a(18) from Vaclav Kotesovec, Dec 19 2021

cp's OEIS Frontend

A289893 Number of maximum independent vertex sets in the n-triangular honeycomb queen graph.

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