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A178660
Numbers k such that k^3 +- (k+5)^2 are primes.
1
7, 12, 13, 18, 58, 142, 187, 502, 597, 657, 702, 907, 912, 942, 943, 972, 1057, 1168, 1248, 1357, 1453, 1533, 1663, 1938, 2013, 2088, 2272, 2373, 2478, 2608, 2848, 2968, 3003, 3028, 3108, 3247, 3423, 3478, 3583, 3817, 3927, 3957, 4132, 4212, 4632, 4668
OFFSET
1,1
LINKS
EXAMPLE
7 is a term since: 7^3 +- 12^2 -> (199,487) which are primes.
MATHEMATICA
Select[Range[8! ], PrimeQ[ #^3-(#+5)^2]&&PrimeQ[ #^3+(#+5)^2]&]
Select[Range[4700], AllTrue[#^3+{(#+5)^2, -(#+5)^2}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Mar 19 2018 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved