A151521 - OEIS

%I #12 Feb 03 2026 23:07:42

%S 1,3,4,13,25,72,166,450,1124,2973,7603,19865,51199,132982,343290,

%T 888309,2292325,5918742,15258937,39329418

%N Number of 2-sided strip polytans (polyaboloes) with n cells.

%H Ed Pegg, Jr., <a href="https://demonstrations.wolfram.com/PolyformExplorer/">Illustrations of polyforms</a>.

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Polyabolo.html">Polyabolo</a>.

%Y Cf. A006074, A151520.

%K nonn,hard,more

%O 1,2

%A _Ed Pegg Jr_, May 13 2009

%E a(6)-a(20) from _John Mason_, Jan 07 2022