Number of 3-element subsets of {1,...,n} whose sum has more than 3 divisors.

Terms

a(0) =0a(1) =0a(2) =1a(3) =2a(4) =6a(5) =11a(6) =22a(7) =35a(8) =55a(9) =78a(10) =110a(11) =145a(12) =192a(13) =245a(14) =312a(15) =386a(16) =476a(17) =572a(18) =684a(19) =804a(20) =943a(21) =1091a(22) =1261a(23) =1442a(24) =1647a(25) =1864a(26) =2108a(27) =2366a(28) =2651a(29) =2951