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%I #21 Nov 03 2024 19:25:53
%S 160,24,27,8,0,0,0
%N Total number of ways a triangle of order n can be completely surrounded by a specific pentiamond.
%C The coronal expansion number is defined to be the number of expansions the central host frame can undergo and still have a corona formed by the coronal tile. The coronal expansion number is 4 for this sequence. See the links section for an example of a pseudo-triangle as the central host frame that has a coronal expansion number of 7. _Craig Knecht_, Oct 31 2024
%H Craig Knecht, <a href="/A376899/a376899_2.png">Pseudo triangle with a coronal expansion number of 7.</a>
%H Craig Knecht, <a href="/A376899/a376899.png">The 160 ways this pentiamond can surround a T1 triangle</a>.
%H Craig Knecht, <a href="/A376899/a376899_1.png">T2, T3, and T4 surrounded by this pentiamond</a>.
%K nonn,more
%O 1,1
%A _Craig Knecht_, Oct 08 2024