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A134003
Positive integers n for which n^2+(n+5)^2 is prime.
1
1, 2, 3, 4, 6, 7, 8, 9, 12, 14, 17, 18, 19, 21, 22, 26, 27, 28, 29, 32, 34, 39, 41, 43, 44, 48, 51, 52, 53, 54, 56, 58, 59, 66, 72, 74, 77, 78, 79, 82, 83, 87, 91, 93, 94, 96, 97, 103, 104, 106, 107, 109, 113, 116, 117, 119, 121, 122, 123, 126, 134, 136, 137, 144, 151, 157
OFFSET
1,2
COMMENTS
Conjecture. If n is in this sequence then n(n+5)=a(a+5)+b(b+5) is not solvable in integers. (This has been verified up to n=500.) See A134002 for the complement of this sequence (in the positive integers).
MATHEMATICA
Select[Range[1, 200], PrimeQ[#^2+(#+5)^2]&] (* Vladimir Joseph Stephan Orlovsky, Feb 02 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
John W. Layman, Oct 01 2007
STATUS
approved