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A064409
Positive even numbers not of the form A001359(i) A006512(j) for integers i and j.
2
2, 4, 6, 14, 20, 26, 28, 32, 38, 40, 44, 50, 52, 56, 58, 62, 68, 70, 74, 80, 82, 86, 88, 92, 94, 96, 98, 100, 104, 110, 116, 118, 122, 124, 128, 130, 134, 136, 140, 146, 148, 152, 158, 160, 164, 166, 170, 172, 176, 178, 182, 188, 190, 194, 200
OFFSET
1,1
COMMENTS
This is different from A007534, which gives positive even numbers which are not the same of a pair of twin primes. The old definition of the present sequence was misleading. - N. J. A. Sloane, Feb 16 2024
LINKS
EXAMPLE
The lesser of the twin primes < 200 are 3, 5, 11, 17, 29, 41, 59, 71, 101, 107, 137, 149, 179, 191, 197 and the greater of the twin primes < 200 are 5, 7, 13, 19, 31, 43, 61, 73, 103, 109, 139, 151, 181, 193, 199. 20 is in the current sequence because no combination of any two numbers from each set just enumerated can be summed to make 20.
MATHEMATICA
p = Select[ Range[ 200 ], PrimeQ[ # ] && PrimeQ[ # 2 ] & ]; q = p 2; Complement[ Table[ n, {n, 2, 200, 2} ], Union[ Flatten[ Table[ p[ [ i ] ] q[ [ j ] ], {i, 1, 15}, {j, 1, 15} ] ] ] ]
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Sep 29 2001
STATUS
approved