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A085554
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Greater of twin primes of the form x^2+2, x^2+4.
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6
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5, 13, 229, 1093, 2029, 3253, 13693, 21613, 59053, 65029, 91813, 140629, 178933, 199813, 205213, 227533, 328333, 567013, 700573, 804613, 815413, 1071229, 2241013, 3629029, 4223029, 4347229, 4809253, 5212093, 5919493, 6185173
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OFFSET
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1,1
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COMMENTS
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Except for the first term, all a(n)=13 (mod 72) with x=3 (mod 6). The lesser of the twin prime pair is given by A253639, the x-values in A086381. - M. F. Hasler, Jan 18 2015
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LINKS
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FORMULA
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MATHEMATICA
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Transpose[Select[Table[x^2+{2, 4}, {x, 5000}], AllTrue[#, PrimeQ]&]][[2]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 15 2015 *)
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PROG
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write(f="b085554.txt", c=1, " 5"); forstep(x=3, 1e6, 6, is_A086381(x)&&write(f, c++" "x^2+4))
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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