A114520 Composites in sequence A114518.

6, 10, 12, 18, 22, 24, 28, 34, 36, 40, 48, 52, 54, 58, 72, 76, 82, 88, 100, 108, 112, 118, 142, 148, 160, 162, 165, 172, 184, 192, 196, 202, 208, 210, 214, 232, 250, 268, 273, 274, 288, 298, 316, 345, 352, 358, 382, 384, 385, 388, 390, 394, 399, 400, 412, 420

Offset: 1

Author

Leroy Quet, Dec 05 2005

Keywords

• nonn

Examples

			24 is a composite. 24 = 2^3 * 3 and 2^3 + 3 = 11, which is prime. So 24 is in the sequence.
		

Crossrefs

Cf. A008475, A114518, A114521, A047820.

Programs

Mathematica

f[n_] := Plus @@ Power @@@ FactorInteger[n]; Select[Select[Range[425], PrimeQ[f[ # ]] &], ! PrimeQ[ # ] &] (* Ray Chandler, Dec 07 2005 *)

PARI

A008475(n)=local(t);if(n<1,0,t=factor(n);sum(k=1,matsize(t)[1],t[k,1]^t[k,2])); for(i=1,700,if(!isprime(i)&&isprime(A008475(i)),print1(i,","))) (Herrgesell)

Extensions

Extended by Ray Chandler and Lambert Herrgesell (zero815(AT)googlemail.com), Dec 07 2005