a(1)=1, a(n)=a(n-1)+n^2 if n odd, a(n)=a(n-1)+ n^4 if n is even.

Terms

a(0) =1a(1) =17a(2) =26a(3) =282a(4) =307a(5) =1603a(6) =1652a(7) =5748a(8) =5829a(9) =15829a(10) =15950a(11) =36686a(12) =36855a(13) =75271a(14) =75496a(15) =141032a(16) =141321a(17) =246297a(18) =246658a(19) =406658a(20) =407099a(21) =641355a(22) =641884a(23) =973660a(24) =974285a(25) =1431261a(26) =1431990a(27) =2046646a(28) =2047487a(29) =2857487