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A111040 Numbers n such that 2*n^2 + 9 is prime. 0
1, 2, 4, 5, 7, 8, 11, 13, 14, 16, 17, 20, 22, 25, 26, 31, 35, 38, 40, 41, 44, 46, 50, 52, 58, 59, 61, 68, 71, 73, 77, 79, 80, 82, 88, 92, 94, 95, 101, 103, 106, 107, 112, 115, 116, 125, 130, 137, 139, 140, 146, 154, 157, 158, 163, 167, 169, 170, 176, 178, 179, 193, 205 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..63.

EXAMPLE

If n=26 then (2*n^2) + 9 = 1361 (prime).

MAPLE

a:=proc(n) if isprime(2*n^2+9)=true then n else fi end: seq(a(n), n=0..280); (Deutsch)

PROG

(PARI) is(n)=isprime(2*n^2+9) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A262978 A112886 A282429 * A191324 A147807 A022559

Adjacent sequences:  A111037 A111038 A111039 * A111041 A111042 A111043

KEYWORD

nonn,easy

AUTHOR

Parthasarathy Nambi, Oct 05 2005

EXTENSIONS

More terms from Emeric Deutsch, Oct 06 2005

STATUS

approved

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Last modified July 15 16:09 EDT 2019. Contains 325049 sequences. (Running on oeis4.)