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Odd composite numbers whose sum of prime factors is prime (counted with multiplicity).
2

%I #12 Aug 14 2024 12:42:49

%S 45,63,75,99,117,147,153,165,175,207,245,273,279,325,333,345,369,385,

%T 399,405,423,435,475,477,507,549,561,567,595,603,651,657,665,675,715,

%U 747,759,775,777,795,833,845,847,867,873,885,891,903,909,925,927,957

%N Odd composite numbers whose sum of prime factors is prime (counted with multiplicity).

%p isA046364 := proc(n)

%p if isprime(n) then

%p false;

%p else

%p isprime(A001414(n))

%p end if;

%p end proc:

%p for n from 3 to 1001 by 2 do

%p if isA046364(n) then

%p printf("%d,",n) ;

%p end if;

%p end do: # _R. J. Mathar_, Aug 14 2024

%t Select[Range[1,957,2], !PrimeQ[#] && PrimeQ[Total[Times@@@FactorInteger[#]]]&] (* _Jayanta Basu_, May 29 2013 *)

%Y Cf. A046363, A046365.

%K nonn

%O 0,1

%A _Patrick De Geest_, Jun 15 1998