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A229271 Numbers n for which n + n' and n - n' are both prime, n' being the arithmetic derivative of n. 3
10, 14, 15, 21, 26, 33, 35, 38, 51, 65, 66, 78, 86, 93, 102, 110, 111, 123, 161, 201, 203, 206, 209, 215, 221, 230, 258, 278, 282, 321, 371, 374, 395, 398, 402, 413, 438, 470, 471, 485, 530, 533, 543, 545, 551, 590, 626, 671, 678, 698, 723, 755, 779, 803, 815 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A165561 and A229269.

LINKS

Paolo P. Lava, Table of n, a(n) for n = 1..1000

MAPLE

with(numtheory); P:=proc(q) local a, n, p; for n from 1 to q do

a:=n*add(op(2, p)/op(1, p), p=ifactors(n)[2]);

if isprime(n+a) and isprime(n-a) then print(n); fi;

od; end: P(10^5);

CROSSREFS

Cf. A003415, A165561, A165562, A229269, A229270, A229272.

Sequence in context: A171156 A235690 A271568 * A088711 A154774 A162708

Adjacent sequences:  A229268 A229269 A229270 * A229272 A229273 A229274

KEYWORD

nonn

AUTHOR

Paolo P. Lava, Sep 18 2013

STATUS

approved

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Last modified July 27 17:57 EDT 2021. Contains 346308 sequences. (Running on oeis4.)