Largest k such that (2^n-k)*2^n-k is a prime number.

Terms

a(0) =1a(1) =5a(2) =9a(3) =29a(4) =61a(5) =119a(6) =249a(7) =507a(8) =1017a(9) =2045a(10) =4047a(11) =8181a(12) =16381a(13) =32765a(14) =65521a(15) =131069a(16) =262137a(17) =524277a(18) =1048567a(19) =2097145a(20) =4194285a(21) =8388597a(22) =16777185a(23) =33554421a(24) =67108821a(25) =134217725a(26) =268435405a(27) =536870909a(28) =1073741811a(29) =2147483619