Smallest k such that in the pairs of numbers j*k +- 1, none is prime for 1 <= j < n but at least one is prime for j = n; or 0 if no such k exists.
A348347
Smallest k such that in the pairs of numbers j*k +- 1, none is prime for 1 <= j < n but at least one is prime for j = n; or 0 if no such k exists.
Terms
- a(0) =1a(1) =5a(2) =92a(3) =13a(4) =208a(5) =47a(6) =512a(7) =149a(8) =1688a(9) =145a(10) =6686a(11) =539a(12) =4106a(13) =757a(14) =9970a(15) =1217a(16) =16012a(17) =881a(18) =56194a(19) =2441a(20) =53576a(21) =3343a(22) =111992a(23) =2917a(24) =152734a(25) =2053a(26) =49376a(27) =6791a(28) =839522a(29) =4985
External references
- oeis: A348347