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A342771
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Primes p such that p, x+y, x-y, p-x*y and p+x*y are prime, where y = p mod 5 and x = (p-y)/5.
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1
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43, 53, 79, 103, 227, 769, 977, 1303, 2179, 2803, 3019, 5179, 5503, 8089, 8101, 10651, 10789, 13339, 13729, 14419, 16069, 17053, 17341, 18077, 23203, 25111, 26153, 26161, 32839, 34127, 34351, 34519, 38791, 39103, 44027, 54319, 56629, 57503, 59053, 60811, 62869, 63079, 64579, 64591, 65203, 69019
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OFFSET
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1,1
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COMMENTS
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If y = 4, x+y = p-x*y.
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LINKS
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EXAMPLE
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a(3) = 79 is a term because y = 79 mod 5 = 4, x = (79-4)/5 = 15, and 15-4 = 11. 15+4 = 19, 79-4*15 = 19 and 79+4*15 = 139 are prime.
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MAPLE
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filter:= proc(n) local a, b;
b:= n mod 5;
a:= (n-b)/5;
isprime(a+b) and isprime(a-b) and isprime(n-a*b) and isprime(n+a*b)
end proc:
select(filter, [seq(ithprime(i), i=1..1000)]);
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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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