A151521 Number of 2-sided strip polytans with n cells.

1, 3, 4, 13, 25, 72, 166, 450, 1124, 2973, 7603, 19865, 51199, 132982, 343290, 888309, 2292325, 5918742, 15258937, 39329418

Offset

1,2

Links

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

Ed Pegg, Jr., Illustrations of polyforms

Eric Weisstein's World of Mathematics, Polytan

Crossrefs

Cf. A006074, A151520.

Sequence in context: A187775 A377310 A295955 * A142860 A111954 A192872

Adjacent sequences: A151518 A151519 A151520 * A151522 A151523 A151524

Keyword

nonn,hard,more

Author

Ed Pegg Jr, May 13 2009

Extensions

a(6)-a(20) from John Mason, Jan 07 2022

Status

approved