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A163492 Numbers such that the two adjacent integers are a perfect square and a prime. 7
1, 2, 3, 8, 10, 24, 48, 80, 82, 168, 224, 226, 360, 440, 442, 728, 840, 1088, 1090, 1224, 1368, 1522, 1848, 2026, 2208, 2400, 3024, 3250, 3720, 3968, 4760, 5040, 5624, 5928, 6562, 7920, 8648, 9802, 10608, 11026, 11448, 12322, 13688, 13690, 14160, 14640 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Also known as the Beprisque numbers.
LINKS
Planet Math, Beprisque numbers
EXAMPLE
a(1) = 2 since 2 lies between 1(square) and 3(prime).
a(2) = 3 since 3 lies between 2(prime) and 4(square).
MATHEMATICA
nn = 100; Sort[Select[Range[0, nn], PrimeQ[#^2 + 2] &]^2 + 1, Select[Range[nn], PrimeQ[#^2 - 2] &]^2 - 1] (* T. D. Noe, Aug 29 2012 *)
Select[Range[15000], AnyTrue[#+{1, -1}, PrimeQ]&&AnyTrue[{Sqrt[#-1], Sqrt[ #+1]}, IntegerQ]&] (* Harvey P. Dale, Feb 06 2023 *)
CROSSREFS
Sequence in context: A329582 A138880 A063474 * A025562 A218910 A107401
KEYWORD
nonn
AUTHOR
Gaurav Kumar, Jul 29 2009
EXTENSIONS
Definition clarified by R. J. Mathar, Aug 08 2009
Number 1 added by WG Zeist, Aug 28 2012
STATUS
approved

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Last modified April 23 22:36 EDT 2024. Contains 371917 sequences. (Running on oeis4.)