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A212430
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Numbers n such that n and n^4 are sums of two twin primes.
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1
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384, 840, 8676, 33300, 34980, 37044, 39984, 42024, 50604, 53760, 55056, 61680, 64380, 71064, 83520, 88176, 97644, 103740, 120204, 129840, 133896, 148764, 154524, 160416, 168120, 173064, 184800, 188880, 199056, 207984, 234744, 266640, 292116, 307044, 356184
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OFFSET
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1,1
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COMMENTS
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All terms are multiples of 12.
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LINKS
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FORMULA
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n/2 +/-1 and (n^4)/2 +/- 1 are primes.
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EXAMPLE
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384=191+193, 384^3=147456=73727+73729.
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MATHEMATICA
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Select[12 Range[30000], AllTrue[{#/2+1, #/2-1, #^4/2+1, #^4/2-1}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Feb 01 2017 *)
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PROG
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(PARI) isok(n) = !(n % 2) && isprime(n/2-1) && isprime(n/2+1) && isprime(n^4/2-1) && isprime(n^4/2+1); \\ Michel Marcus, Oct 19 2013
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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