A305606 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,4

LINKS

Table of n, a(n) for n=1..20.

George Sicherman, Catalogue of Blunt Polytans

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

Adjacent sequences: A305603 A305604 A305605 * A305607 A305608 A305609

KEYWORD

nonn,hard,more

AUTHOR

George Sicherman, Jun 05 2018

EXTENSIONS

a(15)-a(20) from John Mason, Jan 07 2022

STATUS

approved