%I #35 Mar 11 2019 11:42:03

%S 0,0,0,0,0,0,0,0,1,4,25,108,450,1713,6267,21988,75185,251590,828408,

%T 2692630,8661287,27624040,87479663,275392248,862593661,2690285608,

%U 8359581585,25893044920,79978118632,246433568617

%N Number of polyiamonds with n cells, with holes.

%H Craig Knecht, <a href="/A070764/a070764_2.png">Enneiamond with a hole - positions in a triangle.</a>

%H Craig Knecht, <a href="/A070764/a070764_5.png">Hexagon tiling.</a>

%H Craig Knecht, <a href="/A070764/a070764_3.png">Most equal distribution using the polyiamonds with holes.</a>

%H Craig Knecht, <a href="/A070764/a070764.gif">Newton's Cradle.</a>

%H Craig Knecht, <a href="/A070764/a070764_6.png">Polyiamond 12-gon.</a>

%H Craig Knecht, <a href="/A070764/a070764_4.png">Tilings with fixed triangles in a frame.</a>

%Y Equals A000577 - A070765. Cf. A001419, A038144.

%K hard,nonn

%O 1,10

%A _Joseph Myers_, May 05 2002

%E More terms from _Joseph Myers_, Nov 11 2003

%E a(29)-a(30) from _Joseph Myers_, Nov 21 2010