OFFSET
1,2
COMMENTS
a(23) is > 31000.
The A264097(k) are : 3, 3, 3, 15, 3, 45, 9, 105, 9, 165, 297, 177, 1035, 1065, 291, 2403, 2565, 5775, 3975, 459, 915, 3981
MATHEMATICA
With[{nn = 600}, Flatten@ Position[Transpose@ {Table[k = 3; While[! PrimeQ[k 2^n - 1], k += 6]; k, {n, nn}], Table[k = 3; While[! PrimeQ[k 2^n + 1], k += 6]; k, {n, nn}]}, w_ /; SameQ @@ w]] (* Michael De Vlieger, Feb 16 2017 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Pierre CAMI, Feb 15 2017
STATUS
approved