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A157006 Numbers n such that 2^n+5^2 is prime. 0
2, 4, 6, 8, 10, 20, 22, 34, 70, 92, 112, 118, 236, 250, 378, 438, 570, 654, 800, 1636, 2848, 4948, 5670, 6772, 7494, 8006, 9056, 11038 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

For n = 2 2^2 + 25 = 29

For n = 4 2^4 + 25 = 41

For n = 6 2^6 + 25 = 89

MATHEMATICA

Delete[Union[Table[If[PrimeQ[2^n + 25], n, 0], {n, 1, 1000}]], 1]

CROSSREFS

A019434 (2^(2^n)+1) A057733 (2^n+3) A123250 (2^n+5)

A104072 (Primes of the form 2^n+25)

Sequence in context: A078106 A111082 A100433 * A083490 A083498 A172442

Adjacent sequences:  A157003 A157004 A157005 * A157007 A157008 A157009

KEYWORD

nonn

AUTHOR

Edwin Dyke (ed.dyke(AT)btinternet.com), Feb 20 2009

EXTENSIONS

Extended by Vladimir Joseph Stephan Orlovsky, Feb 27 2011

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Last modified February 17 03:37 EST 2012. Contains 205978 sequences.