Number of different fixed (possibly) disconnected pentominoes bounded (not necessarily tightly) by an n*n square.

A162675

Number of different fixed (possibly) disconnected pentominoes bounded (not necessarily tightly) by an n*n square.

Terms

    a(0) =0a(1) =0a(2) =114a(3) =2910a(4) =26490a(5) =145110a(6) =582540a(7) =1891764a(8) =5263020a(9) =13010580a(10) =29297070a(11) =61162530a(12) =119933814a(13) =223098330a(14) =396734520a(15) =678599880a(16) =1121985720a(17) =1800456264a(18) =2813598090a(19) =4293914310a(20) =6415006290a(21) =9401194110a(22) =13538735364a(23) =19188810300

External references