Number of (w,x,y,z) with all terms in {1,...,n} and 2*w*x>=3*y*z.

Terms

a(0) =0a(1) =0a(2) =5a(3) =31a(4) =96a(5) =238a(6) =504a(7) =921a(8) =1585a(9) =2560a(10) =3896a(11) =5698a(12) =8113a(13) =11165a(14) =15042a(15) =19860a(16) =25733a(17) =32814a(18) =41320a(19) =51271a(20) =63015a(21) =76686a(22) =92385a(23) =110397a(24) =131022a(25) =154298a(26) =180579a(27) =210119a(28) =243109a(29) =279810