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A305606
Number of blunt polytans (polyaboloes) with n cells, identifying mirror images. A blunt polytan is one with no acute corners.
0
0, 1, 0, 2, 2, 5, 6, 23, 45, 138, 347, 1007, 2751, 7998, 22638, 65708, 189505, 551798, 1606383, 4697905
OFFSET
1,4
EXAMPLE
There are 3 ditans. Only the square ditan lacks acute corners, so a(2)=1.
CROSSREFS
Cf. A006074, number of polyaboloes with n cells, identifying mirror images.
Sequence in context: A329908 A295198 A080880 * A369634 A120843 A205674
KEYWORD
nonn,hard,more
AUTHOR
George Sicherman, Jun 05 2018
EXTENSIONS
a(15)-a(20) from John Mason, Jan 07 2022
STATUS
approved