Column 5 of array illustrated in A089574 and related to A034261.

Terms

a(0) =1a(1) =18a(2) =101a(3) =357a(4) =978a(5) =2274a(6) =4711a(7) =8954a(8) =15915a(9) =26806a(10) =43197a(11) =67079a(12) =100932a(13) =147798a(14) =211359a(15) =296020a(16) =406997a(17) =550410a(18) =733381a(19) =964137a(20) =1252118a(21) =1608090a(22) =2044263a(23) =2574414a(24) =3214015a(25) =3980366a(26) =4892733a(27) =5972491a(28) =7243272a(29) =8731118