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A140776 A number n is included if (p + n/p) is prime, where p is the largest prime that divides n. 3

%I

%S 2,6,10,12,22,24,28,30,34,40,42,48,52,58,60,66,70,76,78,82,84,88,90,

%T 102,112,118,120,130,132,138,142,148,160,168,172,180,184,186,190,192,

%U 198,202,204,208,210,214,220,222,228,232,234,238,240,246,252,268,270,274

%N A number n is included if (p + n/p) is prime, where p is the largest prime that divides n.

%C All terms are even. - _Robert Israel_, Feb 04 2018

%H Robert Israel, <a href="/A140776/b140776.txt">Table of n, a(n) for n = 1..10000</a>

%e The largest prime dividing 48 is 3. Since 3 + 48/3 = 19 is prime, then 48 is included in this sequence.

%p filter:= proc(n) local p;

%p p:= max(numtheory:-factorset(n));

%p isprime(p+n/p)

%p end proc:

%p select(filter, 2*[$1..1000]); # _Robert Israel_, Feb 04 2018

%t fQ[n_] := Block[{p = Last@ First@ Transpose@ FactorInteger@n}, PrimeQ[p + n/p] == True]; Select[ Range[2, 279], fQ@# &] - _Robert G. Wilson v_, May 30 2008

%Y Cf. A140775, A140777.

%K nonn

%O 1,1

%A _Leroy Quet_, May 29 2008

%E More terms from _Robert G. Wilson v_, May 30 2008

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Last modified January 27 12:22 EST 2022. Contains 350607 sequences. (Running on oeis4.)