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A275415
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Pairs of primes (p, q) such that |2p - 3q| = 1.
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0
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5, 3, 7, 5, 11, 7, 17, 11, 19, 13, 29, 19, 43, 29, 47, 31, 61, 41, 71, 47, 79, 53, 89, 59, 101, 67, 107, 71, 109, 73, 151, 101, 163, 109, 191, 127, 197, 131, 223, 149, 227, 151, 251, 167, 269, 179, 271, 181, 317, 211, 349, 233, 359, 239, 421, 281, 439, 293
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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The first pair (5, 3) is in the sequence because |2*5 - 3*3| = 1;
The second pair (7, 5) is in the sequence because |2*7 - 3*5|= 1.
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MAPLE
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nn:=100:for i from 3 to nn do:
p:=ithprime(i):r:=irem(p, 3):q:=(2*p + (-1)^(r+1))/3:
if isprime(q)
then
printf(`%d, `, p): printf(`%d, `, q):
else
fi:
od:
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PROG
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(PARI) lista(n)=forprime(i=3, n, j=(1.5*i)\1; j+=((j+1)%2); if(isprime(j), print1(j", "i", "))) \\ David A. Corneth, Aug 09 2016
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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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