DLV [build BEN/Oct 11 2007   gcc 4.1.2 20061115 (prerelease) (Debian 4.1.1-21)]

true is bravely true, evidenced by {next(1,2), next(2,3), next(3,4), next(4,5), next(5,6), next(6,7), next(7,8), next(7,11), next(8,9), next(9,10), next(11,12), next(12,13), next(13,14), next(14,15), next(15,16), next(15,19), next(16,17), next(17,18), next(19,20), next(20,21), next(21,22), next(22,23), next(23,24), next(24,25), next(25,26), next(26,27), next(26,38), next(27,28), next(28,29), next(28,36), next(29,30), next(29,33), next(30,31), next(31,32), next(33,34), next(34,35), next(36,37), next(38,39), next(39,40), next(40,41), next(40,48), next(41,42), next(41,45), next(42,43), next(43,44), next(45,46), next(46,47), next(48,49), doAt(startflow,4), doAt(a19,6), doAt(a24,7), doAt(a3,8), doAt(endflow,9), doAt(endflow,17), doAt(endflow,31), doAt(endflow,34), doAt(endflow,36), doAt(endflow,43), doAt(endflow,46), doAt(endflow,48), doAt(a7,11), doAt(a4,12), doAt(a1,13), doAt(a18,14), doAt(a17,15), doAt(a5,16), doAt(a21,19), doAt(a22,20), doAt(a12,21), doAt(a6,22), doAt(a8,23), doAt(a25,24), doAt(a20,25), doAt(a16,26), doAt(a23,27), doAt(a2,28), doAt(a2,40), doAt(a9,29), doAt(a9,41), doAt(a13,30), doAt(a13,42), doAt(a14,33), doAt(a14,45), doAt(a15,38), doAt(a10,39), subsAt(a19,5), ineffset(startflow,x1), ineffset(startflow,x2), ineffset(startflow,x3), ineffset(startflow,x4), ineffset(startflow,x5), ineffset(startflow,x6), ineffset(startflow,x7), ineffset(startflow,x8), ineffset(startflow,x9), ineffset(startflow,x10), ineffset(startflow,x11), ineffset(startflow,x12), ineffset(startflow,x13), ineffset(startflow,x14), ineffset(startflow,x15), ineffset(startflow,x16), ineffset(startflow,x17), ineffset(startflow,x18), ineffset(startflow,x19), ineffset(startflow,x20), ineffset(startflow,x21), ineffset(startflow,x22), ineffset(startflow,x23), ineffset(startflow,x24), ineffset(startflow,x25), ineffset(a19,x5), ineffset(a24,co48), ineffset(a24,co49), ineffset(a3,x5), ineffset(endflow,x7), ineffset(endflow,finished), ineffset(a7,x10), ineffset(a7,x14), ineffset(a4,x16), ineffset(a1,x15), ineffset(a18,x1), ineffset(a18,x15), ineffset(a18,x20), ineffset(a17,co34), ineffset(a17,co35), ineffset(a5,x17), ineffset(a5,x24), ineffset(a21,x7), ineffset(a22,x8), ineffset(a22,x23), ineffset(a12,x2), ineffset(a12,x9), ineffset(a12,x12), ineffset(a12,x22), ineffset(a6,x15), ineffset(a8,x2), ineffset(a8,x5), ineffset(a8,x20), ineffset(a8,x22), ineffset(a25,x10), ineffset(a25,x14), ineffset(a25,x21), ineffset(a20,x13), ineffset(a16,co32), ineffset(a16,co33), ineffset(a23,x3), ineffset(a23,x6), ineffset(a23,x20), ineffset(a23,x24), ineffset(a2,co4), ineffset(a2,co5), ineffset(a9,co18), ineffset(a9,co19), ineffset(a13,x13), ineffset(a13,x24), ineffset(a14,x24), ineffset(a15,x13), ineffset(a10,x7), ineffset(a10,x18), inreadset(a19,x10), inreadset(a19,x14), inreadset(a19,x24), inreadset(a24,x9), inreadset(a24,x11), inreadset(a3,x13), inreadset(endflow,x1), inreadset(endflow,x2), inreadset(endflow,x3), inreadset(endflow,x4), inreadset(endflow,x5), inreadset(endflow,x6), inreadset(endflow,x7), inreadset(endflow,x8), inreadset(endflow,x9), inreadset(endflow,x10), inreadset(endflow,x11), inreadset(endflow,x12), inreadset(endflow,x13), inreadset(endflow,x14), inreadset(endflow,x15), inreadset(endflow,x16), inreadset(endflow,x17), inreadset(endflow,x18), inreadset(endflow,x19), inreadset(endflow,x20), inreadset(endflow,x21), inreadset(endflow,x22), inreadset(endflow,x23), inreadset(endflow,x24), inreadset(endflow,x25), inreadset(a7,x19), inreadset(a4,x21), inreadset(a1,x23), inreadset(a18,x9), inreadset(a18,x22), inreadset(a17,x1), inreadset(a5,x7), inreadset(a5,x11), inreadset(a5,x24), inreadset(a21,x16), inreadset(a22,x23), inreadset(a12,x19), inreadset(a6,x6), inreadset(a6,x18), inreadset(a8,x24), inreadset(a8,x25), inreadset(a25,x3), inreadset(a25,x4), inreadset(a25,x19), inreadset(a20,x9), inreadset(a16,x16), inreadset(a16,x18), inreadset(a23,x10), inreadset(a2,x13), inreadset(a2,x14), inreadset(a2,x18), inreadset(a9,x6), 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impossible(a,23), impossible(a,24), impossible(a,25), impossible(a,26), impossible(a,27), impossible(a,28), impossible(a,40), impossible(a,29), impossible(a,41), impossible(a,30), impossible(a,42), impossible(a,33), impossible(a,45), impossible(a,38), impossible(a,39), impossible(a,18), impossible(a,37), impossible(a,49), impossible(a,32), impossible(a,35), impossible(a,44), impossible(a,47), nextvis(8,9), nextvis(3,8), nextvis(9,10)}