Sequence arising from enumeration of domino tilings of Aztec Pillow-like regions.

Terms

a(0) =0a(1) =1a(2) =5a(3) =19a(4) =59a(5) =161a(6) =405a(7) =967a(8) =2231a(9) =5029a(10) =11153a(11) =24443a(12) =53091a(13) =114505a(14) =245549a(15) =524047a(16) =1113839a(17) =2358989a(18) =4980393a(19) =10485379a(20) =22019675a(21) =46136881a(22) =96468485a(23) =201326039a(24) =419429799a(25) =872414581a(26) =1811938625a(27) =3758095627a(28) =7784627411