Table of number of domino tilings of generalized Aztec pillows of type (1, ..., 1, 3, 1, ..., 1)_n.

Terms

a(0) =1a(1) =1a(2) =5a(3) =1a(4) =10a(5) =25a(6) =1a(7) =17a(8) =65a(9) =113a(10) =1a(11) =26a(12) =146a(13) =346a(14) =481a(15) =1a(16) =37a(17) =292a(18) =932a(19) =1637a(20) =1985a(21) =1a(22) =50a(23) =533a(24) =2248a(25) =5013a(26) =7218a(27) =8065a(28) =1a(29) =65