# A089307 (b-file synthesized from sequence entry) 1 2 2 7 3 61 4 1201 5 15121 6 332641 7 9313921 8 319334401 9 10897286401 10 419026608001 11 14079294028801 12 647647525324801 13 34972966367539201 14 2017671136588800001 15 108416195739371520001 16 6707348643075784704001 17 440955772120958814720001