Numbers k of the form p^2 + 1 (for prime p) where k^2 + 1 is also prime.

Terms

a(0) =10a(1) =26a(2) =170a(3) =1850a(4) =2210a(5) =16130a(6) =69170a(7) =76730a(8) =85850a(9) =113570a(10) =120410a(11) =157610a(12) =196250a(13) =218090a(14) =237170a(15) =253010a(16) =332930a(17) =351650a(18) =368450a(19) =452930a(20) =528530a(21) =537290a(22) =597530a(23) =734450a(24) =786770a(25) =822650a(26) =1329410a(27) =2036330a(28) =2211170