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A064409 Even numbers not the sum of a pair twin primes, one the lesser and the other the greater. 0
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 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

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 above 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

Sequence in context: A138307 A124693 A095698 * A032353 A062112 A084685

Adjacent sequences:  A064406 A064407 A064408 * A064410 A064411 A064412

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 29 2001

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Last modified February 16 10:53 EST 2012. Contains 205904 sequences.