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A160518
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List of pairs of twin primes of the form 2k^3 +- 1.
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2
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431, 433, 18521, 18523, 1940597, 1940599, 3455999, 3456001, 30876497, 30876499, 88723727, 88723729, 105468749, 105468751, 164625749, 164625751, 431999999, 432000001, 451733057, 451733059, 615093749, 615093751, 746495999, 746496001, 1039436927, 1039436929
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OFFSET
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1,1
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COMMENTS
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k is always divisible by 3. For the 5 pairs listed, k = 6, 21, 99, 120 and 249 (see A151612).
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LINKS
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EXAMPLE
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6^3 = 216; 216*2 = 432; both 431 and 433 are prime.
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MAPLE
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isA001359 := proc(n) RETURN(isprime(n) and isprime(n+2)) ; end: for n from 1 to 1000 do twon3 := 2*n^3 ; if isA001359(twon3-1) then printf("%d, %d, ", twon3-1, twon3+1) ; fi; od: # R. J. Mathar, May 29 2009
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MATHEMATICA
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s = Select[54*Range[300]^3, And @@ PrimeQ[# + {-1, 1}] &]; Flatten @
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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Howard Berman (howard_berman(AT)hotmail.com), May 16 2009
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EXTENSIONS
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STATUS
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approved
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