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

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

Offset: 1

Author

Leroy Quet, May 29 2008

Keywords

• nonn

Comments

All terms are even. - Robert Israel, Feb 04 2018

Examples

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

Links

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

Crossrefs

Cf. A140775, A140777.

Programs

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 *)

Extensions

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