Number of (w,x,y,z) with all terms in {0,...,n} and max{w,x,y,z}<2*min{w,x,y,z}.

Terms

a(0) =0a(1) =1a(2) =2a(3) =17a(4) =32a(5) =97a(6) =162a(7) =337a(8) =512a(9) =881a(10) =1250a(11) =1921a(12) =2592a(13) =3697a(14) =4802a(15) =6497a(16) =8192a(17) =10657a(18) =13122a(19) =16561a(20) =20000a(21) =24641a(22) =29282a(23) =35377a(24) =41472a(25) =49297a(26) =57122a(27) =66977a(28) =76832a(29) =89041