Number of rhombuses on a (n+1) X 6 grid.

Terms

a(0) =5a(1) =20a(2) =50a(3) =96a(4) =151a(5) =212a(6) =273a(7) =344a(8) =421a(9) =504a(10) =587a(11) =676a(12) =765a(13) =860a(14) =959a(15) =1064a(16) =1169a(17) =1280a(18) =1391a(19) =1508a(20) =1625a(21) =1748a(22) =1871a(23) =2000a(24) =2131a(25) =2268a(26) =2405a(27) =2548a(28) =2691a(29) =2840