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A111199 Numbers n such that 4k + 9 is prime. 6
1, 2, 5, 7, 8, 11, 13, 16, 20, 22, 23, 25, 26, 32, 35, 37, 41, 43, 46, 47, 55, 56, 58, 62, 65, 67, 68, 71, 76, 77, 82, 85, 86, 91, 95, 97, 98, 100, 103, 106, 110, 112, 113, 125, 128, 133, 137, 140, 142, 146, 148, 151, 152, 158, 161, 163, 166, 167, 173, 175, 181, 187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Solutions of the equation (4*k+9)'=1, where k' is the arithmetic derivative of k. - Paolo P. Lava, Jan 03 2013

LINKS

Daniel Starodubtsev, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A005098(n+1)-2. - R. J. Mathar, Sep 23 2009

EXAMPLE

If k=98 then 4*k + 9 = 401 (prime).

PROG

(PARI) is(n)=isprime(4*n+9) \\ Charles R Greathouse IV, Feb 20 2017

CROSSREFS

Cf. A005098, A095278, A089986, A153238, A144562.

Sequence in context: A189296 A051279 A288464 * A276545 A138671 A286693

Adjacent sequences:  A111196 A111197 A111198 * A111200 A111201 A111202

KEYWORD

nonn

AUTHOR

Parthasarathy Nambi, Oct 24 2005

EXTENSIONS

More terms from R. J. Mathar, Sep 23 2009

STATUS

approved

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Last modified April 3 00:35 EDT 2020. Contains 333195 sequences. (Running on oeis4.)