Third partial sums of seventh powers (A001015).

Terms

a(0) =1a(1) =131a(2) =2577a(3) =23723a(4) =141694a(5) =636426a(6) =2331462a(7) =7323954a(8) =20396871a(9) =51550213a(10) =120271151a(11) =262391493a(12) =540659756a(13) =1060489444a(14) =1992739932a(15) =3605846676a(16) =6310148349a(17) =10717864983a(18) =17722868317a(19) =28605158351a(20) =45165823626a(21) =69899222030a(22) =106210179010a(23) =158685165990