# A048491 (b-file synthesized from sequence entry) 0 1 1 10 2 28 3 64 4 136 5 280 6 568 7 1144 8 2296 9 4600 10 9208 11 18424 12 36856 13 73720 14 147448 15 294904 16 589816 17 1179640 18 2359288 19 4718584 20 9437176 21 18874360 22 37748728 23 75497464 24 150994936 25 301989880 26 603979768 27 1207959544 28 2415919096