A179892 Numbers which are not the sum of three distinct members of twin primes.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120

Offset: 1

Author

Zak Seidov, Jul 30 2010

Keywords

• nonn

Comments

All positive even numbers are terms of the sequence:

members of twin primes are odd and the sum of three odd primes is odd.

No odd numbers >=19 are in the sequence (conjecture?).

Examples

			15=3+5+7, 19=3+5+11 hence 15 and 19 are not in the sequence.
		

Crossrefs

Cf. A007534 Even numbers which are not the sum of a pair of twin primes.

Programs

Mathematica

pr=Prime[Range[100]];se=Select[pr,PrimeQ[ #-2]||PrimeQ[ #+2]&];
se2=Select[Union[Total/@Subsets[se,{3}]],#<200&];Complement[Range[200],se2]