Let M(n) be the n X n matrix m(i,j)=min(i,j) for 1<=i,j<=n; then a(n) is the trace of M(n)^(-7).

Terms

a(0) =1a(1) =843a(2) =3827a(3) =7252a(4) =10684a(5) =14116a(6) =17548a(7) =20980a(8) =24412a(9) =27844a(10) =31276a(11) =34708a(12) =38140a(13) =41572a(14) =45004a(15) =48436a(16) =51868a(17) =55300a(18) =58732a(19) =62164a(20) =65596a(21) =69028a(22) =72460a(23) =75892a(24) =79324a(25) =82756a(26) =86188a(27) =89620a(28) =93052a(29) =96484