a(n) = [ (3rd elementary symmetric function of S(n))/(first elementary symmetric function of S(n)) ], where S(n) = {first n+2 positive integers congruent to 1 mod 3}.

A024220

a(n) = [ (3rd elementary symmetric function of S(n))/(first elementary symmetric function of S(n)) ], where S(n) = {first n+2 positive integers congruent to 1 mod 3}.

Terms

    a(0) =2a(1) =19a(2) =71a(3) =188a(4) =410a(5) =784a(6) =1367a(7) =2226a(8) =3435a(9) =5078a(10) =7249a(11) =10049a(12) =13589a(13) =17990a(14) =23380a(15) =29897a(16) =37689a(17) =46911a(18) =57728a(19) =70315a(20) =84854a(21) =101537a(22) =120566a(23) =142150a(24) =166508a(25) =193869a(26) =224469a(27) =258554a(28) =296380a(29) =338210

External references