# A058756 (b-file synthesized from sequence entry) 0 1 1 -2 2 -2 3 -2 4 -6 5 -10 6 -34 7 -82 8 -254 9 -730 10 -2238 11 -6826 12 -21370 13 -67122 14 -213654 15 -684258 16 -2208694 17 -7169298 18 -23402738 19 -76748130 20 -252790518 21 -835816658 22 -2773236614 23 -9230776706 24 -30814377058 25 -103139338858 26 -346067984622 27 -1163810570178