

A140776


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


3



2, 6, 10, 12, 22, 24, 28, 30, 34, 40, 42, 48, 52, 58, 60, 66, 70, 76, 78, 82, 84, 88, 90, 102, 112, 118, 120, 130, 132, 138, 142, 148, 160, 168, 172, 180, 184, 186, 190, 192, 198, 202, 204, 208, 210, 214, 220, 222, 228, 232, 234, 238, 240, 246, 252, 268, 270, 274
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OFFSET

1,1


COMMENTS

All terms are even.  Robert Israel, Feb 04 2018


LINKS

Robert Israel, Table of n, a(n) for n = 1..10000


EXAMPLE

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


MAPLE

filter:= proc(n) local p;
p:= max(numtheory:factorset(n));
isprime(p+n/p)
end proc:
select(filter, 2*[$1..1000]); # Robert Israel, Feb 04 2018


MATHEMATICA

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


CROSSREFS

Cf. A140775, A140777.
Sequence in context: A071638 A028348 A214963 * A277238 A108783 A235989
Adjacent sequences: A140773 A140774 A140775 * A140777 A140778 A140779


KEYWORD

nonn


AUTHOR

Leroy Quet, May 29 2008


EXTENSIONS

More terms from Robert G. Wilson v, May 30 2008


STATUS

approved



