a(n) = n*(n+1) + (n+2)*(n+3) + (n+4)*(n+5).

Terms

a(0) =26a(1) =44a(2) =68a(3) =98a(4) =134a(5) =176a(6) =224a(7) =278a(8) =338a(9) =404a(10) =476a(11) =554a(12) =638a(13) =728a(14) =824a(15) =926a(16) =1034a(17) =1148a(18) =1268a(19) =1394a(20) =1526a(21) =1664a(22) =1808a(23) =1958a(24) =2114a(25) =2276a(26) =2444a(27) =2618a(28) =2798a(29) =2984