Prime number spiral (clockwise, Northwest spoke).

Terms

a(0) =2a(1) =23a(2) =97a(3) =227a(4) =419a(5) =661a(6) =1009a(7) =1427a(8) =1879a(9) =2437a(10) =3083a(11) =3803a(12) =4637a(13) =5519a(14) =6481a(15) =7573a(16) =8737a(17) =9931a(18) =11321a(19) =12743a(20) =14327a(21) =15877a(22) =17609a(23) =19471a(24) =21391a(25) =23327a(26) =25469a(27) =27739a(28) =30047a(29) =32429