Least positive integer k such that (k-1)^2+(k*n)^2, k^2+(k*n-1)^2, (k+1)^2+(k*n)^2 and k^2+(k*n+1)^2 are all prime.
A261382
Least positive integer k such that (k-1)^2+(k*n)^2, k^2+(k*n-1)^2, (k+1)^2+(k*n)^2 and k^2+(k*n+1)^2 are all prime.
Terms
- a(0) =2a(1) =2510a(2) =15a(3) =30a(4) =5a(5) =510a(6) =730a(7) =440a(8) =195a(9) =6230a(10) =2040a(11) =2760a(12) =20a(13) =1010a(14) =12570a(15) =31340a(16) =1625a(17) =1650a(18) =725a(19) =2480a(20) =2160a(21) =520a(22) =1055a(23) =60a(24) =5a(25) =20a(26) =1260a(27) =25800a(28) =6185a(29) =6240
External references
- oeis: A261382