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A144938
Squares k such that k - 2 and k + 2 are prime.
7
9, 81, 225, 441, 1089, 13689, 56169, 74529, 91809, 95481, 149769, 184041, 194481, 199809, 263169, 314721, 328329, 370881, 651249, 804609, 1071225, 1147041, 1238769, 1306449, 1520289, 1535121, 1718721, 2442969, 2595321, 2614689
OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
A087679 intersect A000290. - R. J. Mathar, Dec 11 2020
MATHEMATICA
lst={}; Do[p=n^2; If[PrimeQ[p-2]&&PrimeQ[p+2], AppendTo[lst, p]], {n, 1, 7!, 2}]; lst
PROG
(PARI) forstep(n=3, 1e3, 6, if(isprime(n^2-2)&&isprime(n^2+2), print1(n^2", "))) \\ Charles R Greathouse IV, Oct 05 2011
CROSSREFS
Sequence in context: A207565 A207758 A016946 * A208114 A208119 A207369
KEYWORD
nonn,easy
AUTHOR
STATUS
approved