//的输出/demo/seq/A309807-demo.cc：//描述：//%OEIS序列A309807：//%[n]的置换数σ，使得p（k）/k>p（k+1）/（k+1。参数1:7==n[{1，2，…，n}的排列]默认值=7A309807：1: [ 2 3 4 5 6 7 1 ]2: [ 3 4 5 6 7 2 1 ]3: [ 3 5 6 7 4 2 1 ]4: [ 3 5 7 6 4 2 1 ]5:[4 5 6 7 3 2 1]6: [ 4 5 7 6 3 2 1 ]7: [ 4 6 7 5 3 2 1 ]8: [ 4 7 5 6 3 2 1 ]9: [ 4 7 6 5 3 2 1 ]10: [ 5 6 7 4 3 2 1 ]11: [ 5 7 6 4 3 2 1 ]12: [ 6 5 7 4 3 2 1 ]13: [ 6 7 4 5 3 2 1 ]14: [ 6 7 5 4 3 2 1 ]15: [ 7 3 4 5 6 2 1 ]16: [ 7 4 5 6 3 2 1 ]17: [ 7 5 6 4 3 2 1 ]18: [ 7 6 4 5 3 2 1 ]19: [ 7 6 5 4 3 2 1 ]ct=19ct=19