Number of 7-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero and first differences in -n..n.

A209035

Number of 7-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero and first differences in -n..n.

Terms

    a(0) =6a(1) =86a(2) =576a(3) =2517a(4) =8235a(5) =22249a(6) =52208a(7) =110285a(8) =214440a(9) =390344a(10) =672932a(11) =1108883a(12) =1758433a(13) =2698447a(14) =4024458a(15) =5854361a(16) =8330650a(17) =11624758a(18) =15939472a(19) =21513945a(20) =28626249a(21) =37599103a(22) =48802532a(23) =62660333a(24) =79652814a(25) =100324030a(26) =125284570

External references