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A217991
Numbers n such that n^16+1 and (n+2)^16+1 are both prime.
0
74, 156, 474, 476, 686, 688, 774, 776, 830, 832, 982, 2698, 3560, 3646, 4016, 5974, 8542, 8732, 10730, 10858, 12164, 12902, 13022, 13154, 13554, 13838, 13840, 20436, 20454, 20504, 21912, 24554, 24770, 25582, 30144, 31634, 31882, 32358, 32360, 32992, 33758
OFFSET
1,1
EXAMPLE
74 is in the sequence because 74^16+1 = 808551180810136214718004658177 and 76^16+1 = 1238846438084943599707227160577 are both prime.
MATHEMATICA
lst={}; Do[p=n^16+1; q=(n+2)^16+1; If[PrimeQ[p] && PrimeQ[q], AppendTo[lst, n]], {n, 0, 34000}]; lst
Select[Range[34000], AllTrue[{#^16+1, (#+2)^16+1}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jun 24 2015 *)
CROSSREFS
Cf. A006313.
Sequence in context: A365201 A044325 A044706 * A105053 A260171 A044406
KEYWORD
nonn,easy
AUTHOR
Michel Lagneau, Oct 17 2012
STATUS
approved