A151538 Number of 1-sided strip polyedges with n cells.

1, 2, 6, 14, 40, 102, 284, 752, 2069, 5547, 15134, 40712, 110456, 297066, 802808, 2156378, 5810329, 15584271, 41894990, 112217372, 301115391, 805584175, 2158366236, 5768337730, 15435275815, 41214200699, 110164972820, 293922598172, 784925297952, 2092745480990, 5584229143243

Offset: 1

Author

Ed Pegg Jr, May 13 2009

Keywords

• nonn
• hard

Comments

With A001411 as main input and counting the symmetrical shapes separately, higher terms can be computed efficiently (see formula). - Bert Dobbelaere, Jan 07 2019

Links

• Bert Dobbelaere, Table of n, a(n) for n = 1..60
• Ed Pegg, Jr., Illustrations of polyforms
• Eric Weisstein's World of Mathematics, Polyedge

Crossrefs

Cf. A001411, A019988, A037245, A151537, A323189 (program).

Formula

a(n) = (A001411(n) + A323189(n)) / 8. - Bert Dobbelaere, Jan 07 2019

Extensions

a(13)-a(19) from Joseph Myers, Oct 03 2011

More terms using formula by Bert Dobbelaere, Jan 07 2019