A229271 - OEIS

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A229271

Numbers n for which n + n' and n - n' are both prime, n' being the arithmetic derivative of n.

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);