a(n) = Sum_{k=1..n} k^2 * tau(k)^2, where tau is A000005.

Terms

a(0) =1a(1) =17a(2) =53a(3) =197a(4) =297a(5) =873a(6) =1069a(7) =2093a(8) =2822a(9) =4422a(10) =4906a(11) =10090a(12) =10766a(13) =13902a(14) =17502a(15) =23902a(16) =25058a(17) =36722a(18) =38166a(19) =52566a(20) =59622a(21) =67366a(22) =69482a(23) =106346a(24) =111971a(25) =122787a(26) =134451a(27) =162675a(28) =166039a(29) =223639