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A352605
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Primes p such that the floor of the area of a triangle with sides p-1, p and p+1 is prime.
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1
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3, 41, 97, 127, 163, 179, 239, 277, 367, 439, 443, 541, 569, 571, 577, 593, 677, 719, 809, 877, 1013, 1087, 1201, 1259, 1439, 1553, 1601, 1609, 1721, 1871, 1879, 1889, 2063, 2143, 2179, 2273, 2281, 2689, 2803, 2819, 2887, 3137, 3313, 3511, 3527, 3637, 3797, 3847, 3911, 4049, 4091, 4441, 4933
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OFFSET
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1,1
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COMMENTS
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Primes p such that floor(p*sqrt(3*(p^2-4))/4) is prime.
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LINKS
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EXAMPLE
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a(3) = 97 is a term because 97 is prime, the area of a triangle with sides 96, 97 and 98 is 4073.35..., and 4073 is prime.
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MAPLE
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filter:= p -> isprime(floor(p/4*sqrt(3*(p^2-4)))):
select(filter, [seq(ithprime(i), i=1..10000)]);
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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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