OFFSET
1,1
COMMENTS
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
FORMULA
EXAMPLE
a(1) = 79 because prevprime(79) + nextprime(79) = 73 + 83 = 156 = 13 * 12.
a(2) = 103 because prevprime(103) + nextprime(103) = 101 + 107 = 208 = 13 * 16.
a(3) = 139 because prevprime(139) + nextprime(139) = 137 + 149 = 286 = 13 * 22.
a(4) = 233 because prevprime(233) + nextprime(233) = 229 + 239 = 468 = 13 * 36.
MATHEMATICA
Prime@ Select[Range[2, 496], Mod[Prime[ # - 1] + Prime[ # + 1], 13] == 0 &] (* Robert G. Wilson v *)
Select[Partition[Prime[Range[500]], 3, 1], Divisible[#[[1]]+#[[3]], 13]&] [[All, 2]] (* Harvey P. Dale, Apr 06 2022 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Jan 01 2006
EXTENSIONS
More terms from Robert G. Wilson v, Jan 05 2006
STATUS
approved