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A179892 Numbers which are not the sum of three distinct members of twin primes. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

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?).

LINKS

Table of n, a(n) for n=1..68.

EXAMPLE

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

MATHEMATICA

pr=Prime[Range[100]]; se=Select[pr, PrimeQ[ #-2]||PrimeQ[ #+2]&];

se2=Select[Union[Total/@Subsets[se, {3}]], #<200&]; Complement[Range[200], se2]

CROSSREFS

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

Sequence in context: A325044 A303550 A164563 * A061773 A125007 A290748

Adjacent sequences:  A179889 A179890 A179891 * A179893 A179894 A179895

KEYWORD

nonn

AUTHOR

Zak Seidov, Jul 30 2010

STATUS

approved

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Last modified October 19 13:01 EDT 2019. Contains 328222 sequences. (Running on oeis4.)