Sum of seventh powers of unitary divisors.

Terms

a(0) =1a(1) =129a(2) =2188a(3) =16385a(4) =78126a(5) =282252a(6) =823544a(7) =2097153a(8) =4782970a(9) =10078254a(10) =19487172a(11) =35850380a(12) =62748518a(13) =106237176a(14) =170939688a(15) =268435457a(16) =410338674a(17) =617003130a(18) =893871740a(19) =1280094510a(20) =1801914272a(21) =2513845188a(22) =3404825448