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A070764 Number of polyiamonds with n cells, with holes. 5
0, 0, 0, 0, 0, 0, 0, 0, 1, 4, 25, 108, 450, 1713, 6267, 21988, 75185, 251590, 828408, 2692630, 8661287, 27624040, 87479663, 275392248, 862593661, 2690285608, 8359581585, 25893044920, 79978118632, 246433568617 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,10

LINKS

Table of n, a(n) for n=1..30.

Craig Knecht, Enneiamond with a hole - positions in a triangle.

Craig Knecht, Hexagon tiling.

Craig Knecht, Most equal distribution using the polyiamonds with holes.

Craig Knecht, Newton's Cradle.

Craig Knecht, Polyiamond 12-gon.

Craig Knecht, Tilings with fixed triangles in a frame.

CROSSREFS

Equals A000577 - A070765. Cf. A001419, A038144.

Sequence in context: A329495 A042651 A225692 * A327646 A244746 A110051

Adjacent sequences:  A070761 A070762 A070763 * A070765 A070766 A070767

KEYWORD

hard,nonn

AUTHOR

Joseph Myers, May 05 2002

EXTENSIONS

More terms from Joseph Myers, Nov 11 2003

a(29)-a(30) from Joseph Myers, Nov 21 2010

STATUS

approved

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Last modified October 16 07:07 EDT 2021. Contains 348041 sequences. (Running on oeis4.)