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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
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 4 09:10 EST 2021. Contains 349484 sequences. (Running on oeis4.)